This is a list I've been compiling in my head pretty much since the release of Brawl of characters, stages and concepts I'd love to see in the next iteration. The list may seem daunting (and it IS), but really I'd only expect a fraction of content to actually be in the game compared to the list I made, and some are just personal choices rather than actually popular things. Also I infrequently add stuff to the list, I didn't do this all in one day. I'm not THAT crazy, just mostly crazy.
Costumes and edits for Existing People:
-Mario: Dr. Mario (Changes fireballs to pellets and fire effects to lightning)
-Luigi: Mr. L - Possible Down Special change to Vaccuum?
-Peach: Sports Gear OR Rosalina
-Bowser: Dry Bowser
-Wario: Classic
-Yoshi: Boshi
-Meta Knight: Maskless or Galacta Knight
-King Dedede: Masked Dedede - New Final Smash: Dark Matter Possession OR Ultra Hammer Spin
-Lucas: Suit - New Final Smash: PK Love
-Ness: Pajamas - New Final Smash: PK Rockin
-Samus: Fusion/Justin Bailey
-Donkey Kong: Funky Kong gear
-Diddy Kong: Backwards cap and sunglasses or DK Jr gear
-Fox: Assault gear
-Falco: Assault gear - New Final Smash: Arwing
-Wolf: Classic 64 Gear
-Pikachu: Raichu?
-Jigglypuff: Clefairy?
-Mewtwo: Armored
-Lucario: Hat and cape?
-Pokemon Trainer: Team Rocket Gear (Skull mask on Charizard, Sunglasses on Squirtle, Helmet on Ivysaur?)
-Captain Falcon: Unmasked OR Phoenix
-Olimar: Tuxedo?
-Pit: Putt OR Armored
-Mr. Game & Watch: More Defined
-Link: Dark Link OR Zora Armor
-Toon Link: Regular Clothes
-Zelda: Cloaked?
-Ganondorf: OOT
-Marth: Anri OR Myrmidon Gear
-Roy: Eliwood OR Mercenary gear
-Ike: Black Knight
-Ice Climbers: Beach Gear
-ROB: Ancient Minister
-Snake: Naked Snake or Old Snake
-Sonic: Classic
Mario Series
Playables:
-Waluigi: Strikers Costume
N - Whirluigi
F - Liar Ball
U - Air Swim
D - Motorcycle Doughnuts
FS - Wall-Luigi!
-Bowser Jr.: Dry Bowser Jr. OR Shadow Mario
N - Fireball
F - Paint Blob
U - Mini Clown Car
D - Spiky Shield
FS - Bowser Jr.'s Airship
Special Notes: Certain attacks utilizing his Paintbrush can rarely give some sort of status ailment. The paint on the tip changes with every Paint Blob attack.
-Geno: Updated Costume
N - Geno Beam
F - Geno Whirl
U - Geno Boost
D - Geno Blast
FS - Geno Flash
-Mallow: Crowned
N - Snowy
F - Shocker
U - Nimbus Royal Bus
D - Star Rain
FS - Prince Crybaby
-Booster: Dressed like Mario or Wario (Either classic or sports wear)
N - Snifit Cannon
F - Booster Train
U - Grate Guy Ball
D - Bad Breath
FS - Spritz Bomb
-Smithy: Powered Up
N - Treasure Head
F - Tank Head
U - Magician Head
D - Sledge
FS - Dark Star
Special Notes: His head becomes the Shield head when he blocks
-Fawful: Antennae Costume
N - Laser Gun
F - Vaccuum Helmet
U - Helmet Rocket
D - Fawful Shield
FS - Dark Fawful
Throw - Grabby Gun
Special Notes: If hit hard enough while Helmet is in use, it can be knocked off, preventing Helmet functions
-Paper Mario:
-Shy Guy (Joke Character): Fawful Guy OR Fedora
N - Slingshot - Fires a small pebble or fires held item. Can be aimed various directions and held for greater distance, but the slingshot can snap.
F - Bullet Bill Ride - Dashes forward on a Bullet Bill
U - Helicopter
D - Pogo Stick
FS - Lightning Dance
Assist Trophies:
-Croco: Steals items and throws Bobombs and Poison Mushrooms
-Fawful: Flies around via his helmet-jetpack and uses it to spit out poisonous gas
-Yaridovich: Stabs enemies with standard spear, does massive knockback if his head is attached, and if he is smashed he breaks into numerous Drill Bits that hop around the screen.
-Johnny Jones: Dives offscreen and flies up from the bottom several times either attacking with his hook or his trident.
-Booster: Rides around on his train throwing Bobombs
-Wart (8-Bit): Spits out bubbles.
-Kamek: Either attacks with magic (that does random effects to enemies), or flies over the arena on his broom, making the user Giant and the enemies Tiny.
Items:
-Gold Mushroom (Mario Kart): Makes user giant and invincible
-Giant Goomba Shoe (Whatever it's called, the one that jumps high): Operates a lot like SMB3 version. Absorbs damage and eventually knocks off after damaged enough.
-Koopa Clown Car
Story Enemies:
-Fawfulized enemies from other games (I love that idea)
-SMB2 Enemies
Story Bosses:
-Clown Car
-Smithy
-Koopa Kids (Secret Battle, all consecutively or all at once)
-Tatanga
-Culex (Secret battle)
Stages:
-Some sort of Galaxy related stage
-Bowser's Castle
-Bowser's Body (Mario and Luigi 3)
- Bowser's Armada
Zelda Series
Playables:
-Toon Zelda (Transforms into Tetra, Final Smash has her transfered to one of those big armors from Spirit Tracks)
-Majora's Mask Skull Kid: Majora
-Majora's Mask Young Link (New Moveset, uses masks for specials, not to become other characters entirely)
-Toon Link with new moves (If no Majora's Mask Young Link): Outset Outfit
-Midna: Unmasked
-Byrne: Unmasked
-Ganon (Pig): OOT Pig
-Vaati: Agahnim gear
-Tingle (Joke Character)
Assist Trophies:
-Wind Fish
-Gato: Runs around slicing with swords and dropping bombs.
-Aquamentus (8-bit): Spits fireballs in spread patterns.
-Onox: Swings his mace around in a wide pattern
Items:
-Biggoron Sword: A heavy-damaging, slow swinging weapon.
-Giant's Knife: Same thing as Biggoron Sword, but breaks quickly.
-Longshot: Grabs enemies from a long distance for a throw attack.
-Bombchu - Crawls across the stage and explodes. Climbs walls.
Story Enemies:
-Like-Like
-Redead
-Stalfos
-Moblin
Story Bosses:
-Volvagia
-Dark Nut
-Stallord
-Any evil pawn character
Stages:
-Hyrule Castle / Golden Pyramid (from A Link to the Past)
-Ghost Ship
-Death Mountain
Kirby Series
Playables:
-Marx: Marx Soul
-Knuckle Joe: Megaton Punch Gear
N - Smash Punch
F - Shining Kick
U - Rising Break
D - Megaton Punch
FS - Shining Megaton Punch
-Gooey
-Daroach: Spinni Gear
-Bandana Waddle Dee: Sailor Hat Waddle Dee
N - Beam
F - Spear Toss
U - Parasol
D - Spike Helmet
FS - Bomber Attack
Assist Trophies:
-Kracko: Flies around either shooting sparks, dropping rain, dropping Waddle Doos and shooting lightning
-Bonkers: Runs around swinging his hammer and throwing coconut bombs
-Bio Spark: Fires shurikens and performs a heavy hitting throw attack if close to enemy. Retaliates with a teleporting jump kick if hit.
-Dyna Blade: Flies into background and then flies at the enemy.
-Marx (If not playable): Either drops an Ice Bomb, plants Ivy Pillars or makes a Black Hole.
-NOVA: Grants the user a random positive attribute. (Invincibility, Golden Hammer, Giant, Bunny Hood)
-Lolo and Lala: Pushes around blocks and Gordies
Items:
-Hydra: 3-piece weapon. Gives 3 powerful shots instead of one insta-kill like Dragoon.
-Triple Star: Fires a spread of three stars that then return to the rod.
Story Enemies:
-The Squeaks
-Waddle Dee
-Waddle Doo
-Dark Matter
-Blade and Sword Knights
-Biospark
-Mr. Frosty
-Bonkers
Story Bosses:
-Possessed Dedede: Essentially DeDeDe's fight from KDL3 and K64
-Dark Matter / 0 / 0^2
-Overpowered Whispy Woods: Mad looking Whispy Woods that shoots homing tornados, drops bombs instead of apples, and can spit a powerful attack from his mouth.
Stages:
-Fountain of Dreams (New stage design?)
-Dedede's Arena
Metroid
Playables:
-Ridley: Meta Ridley
N - Fire Ball
F - Jaw Crusher
U - Flight
D - Talon Crusher
FS - Omega Ridley
-Sylux
N - Shock Coil
F - Shock Skewer
U - Lockjaw Screw
D - Tripwire
FS - Delano 7
-Rundas
-Weavel
-Dark Samus (or as alt costume): Transparent
N - Phazon Beam (Freezes when fully charged)
F - Phazon Charge
U - Boost Ball
D - Phazon Pillar
FS- Metroid Prime OR Phazon Beam
-Anthony: No Helmet
Assist Trophies:
-Spire: Rolls around the field
-One of those Federation marine guys: Basic run and gun assistance.
-Dark Samus (If not playable): Teleports around firing rapidly, or performs one big crash attack.
-Ridley (If not playable): Flies around breathing fire and picking enemies up to slam them down.
-Phantoon: Flies around and swipes with his tentacles. Cannot be hit.
-Kraid (8-bit): Fires various 8-bit projectiles.
Items:
(No ideas)
Story Enemies:
-Metroid
-Zoomer
-Skree
-Side Hopper
-Ki Hunter
-Space Pirate
Story Bosses:
-Mother Brain (Containment Tank and Giant Body)
-Kraid
-Metroid Prime (Both Forms)
-SA-X (Taking other fighter forms)
-Queen Metroid (Other Metroid forms fought through the course of the game) (Secret Boss)
Pokemon
Playables:
-Meowth: Giovanni Trenchcoat
N - Pay Day
F - Feint
U - Fury Swipes
D - Dig
FS - Thunderbolt Cannon (Performs Thunderbolt with a gun rather than actually using it)
-Plusle and Minun (Duo character)
-Better version of Mewtwo: Armored
N - Shadow Ball
F - Psycho Cut
U - Teleport
D - Disable
FS - Psystrike
Colors: Purple, Green (Shiny), Black (PS2 Shiny), Pink (R/B Colored), Dark (Dark Lugia Coloration)
-Scizor
N - Bullet Punch
F - X-Scissor
U - Steel Wing
D - Razor Wind
FS - Flash Cannon
-Deoxys (Changes into forms for different moves, not as different characters): Giygas Influence
N - Psycho Boost - In Normal Form
F - Zap Cannon - In Attack Form
U - Extreme Speed - In Speed Form
D - Iron Defense - In Defense Form
FS - Hyper Beam
-Infernape
N - Flame Wheel
F - Mach Punch
U - Acrobatics - If Infernape is holding an item, the attack power is reduced.
D - Fire Spin
FS - Blast Burn
-Gallade
N - Leaf Blade
F - Magical Leaf
U - Double Team - Splits into two afterimages, only one of which is revealed to be real.
D - Heal Pulse - Charges up for several seconds and then heals a very small amount of damage.
FS - Stored Power
-Darkrai
N - Dark Void
F - Dream Eater
U - Ominous Wind
D - Dark Pulse
FS - Nightmare
-Zoroark (Actually don't like this idea, but doesn't it seem inevitable?): Team Plasma Costume
N - Night Daze
F - Pursuit
U - U-Turn
D - Illusion
FS - Midnight Daze
-Scrafty: Hood Up
N - Sludge Bomb
F - Head Smash
U - High Jump Kick
D - Focus Punch - Charges up, and if the next tap of B is timed correctly, it does massive damage.
FS - Scary Face - Getting close to Scrafty causes enemies to turn and flee, giving him a chance to hit their backs
-Nidoking (Personal favorite, no real reason)
-Bisharp (Same with this): Grimsley Costume
N - Metal Burst - Does damage around Bisharp. Does extra damage if timed as a counter to an attack
F - Stone Edge - A hard kick that knocks up sharp rocks
U - Night Slash - Pauses and then quickly slashes in selected direction
D - Metal Sound - Summons up to three Pawniards. Only one at start, slowly builds up, doesn't reset with death. Pawniards can be thrown, and if seperated from the pack they become weaker.
FS - Swords Dance - Summons all Pawniards and exponentially raises attack for all of them.
-2nd Trainer with another 3 set, such as:
-Lyra (Chikorita, Quilava, Feraligatr OR Cyndaquil, Croconaw, Meganium)
-May (Mudkip, Grovyle, Blaziken OR Torchic, Marshtomp, Sceptile)
-Dawn (Turtwing, Monferno, Empoleon OR Turtwig, Prinplup, Infernape)
-Cheren (Oshawott, Servine, Emboar OR Snivy, Pignite, Samurott)
-Silver (Sneasel, Gengar, Feraligatr)
-N (Purrloin, Scrafty, Zoroark)
-Alder (Accelgor and Escavalier)
Items:
Pester Ball
Master Ball - Always guarantees a Legendary Pokemon
Story Enemies: (These are kind of arbitrary, there's a lot to work with)
-Spearow
-Zubat
-Geodude
-Diglet
-Steelix
-Donphan
-Dustox
-Mawile
-Drifblim
-Rotom
-Golurk
-Pawniard
Story Bosses:
-Lance (With Dragonite(s?)
-Cynthia (With Garchomp)
-N (With Reshiram and/or Zekrom)
-Ghetsis (With Hydreigon)
-Dialga, Palkia or Giratina (or any combination)
-Regigigas (Secret)
Stages:
-N's Castle
-Mt Silver
-Safari Zone
-Spear Pillar / Distortion World (Updated Spear Pillar)
Star Fox
Playables:
-Slippy Toad: Classic
N - Grenade
F - Homing Launcher
U - Jetpack
D -Fireburst Pod
FS - Demon Launcher
-Krystal: Assault
N - Ice Blaster
F - Fire Blaster
U - Rocket Boost
D - Super Quake
FS - Demon Rifle
-Dash Bowman: Andross gear
N - Venomian Shock
F - Venomian Dash
U - Venomian Flight
D - Venomian Shield
FS - Legacy of Andross -
-General Scales
-Pigma: Cyborg (Joke Character)
Assist Trophies:
-Andross (Classic): Spits polygon rectangles from the background
-Arwing/Wolfen Team: Swoop in and fire at the enemy
Story Enemies:
-Generic animal people grunts
-Various vehicles and armaments
Story Bosses:
-Andross
-Attack Carrier
Stages:
-Venom Core
-Sector X
-Corneria
Donkey Kong
Playables:
-King K. Rool: Kaptain
N - Blunderbluss
F - Krown Throw
U - Barrel Rocket
D - Khameleon Kloak
FS - KAOS Mk. II
-Dixie (and Kiddie?) Kong: Tiny and Chunky gear
-Lanky Kong: Underwear
-Funky Kong (Possibly just an alternate costume for DK): Classic
-Cranky Kong (Joke Character): Boxing Coach
Assist Trophies:
-Krusha
-Koindozer
-Candy Kong
-Kalypso
Items:
-Klobber (that one that hides in barrels)
-Orange Grenade
Story Enemies:
-Kritter
-Krusha
-Klump
-Cat o' Ninetails
-Zinger
-Gnawty
-Something new I'm not familiar with
Story Bosses:
-KAOS
-Klubba
-Tiki Tong
-Ghastly King (Secret Boss)
Stages:
F-Zero
Playables:
-Samurai Goroh: Armor?
-Black Shadow: Deathborn
Assist Trophies:
-Dai Goroh
-Zoda
-Pico
Story Enemies:
-Death Soldiers
Earthbound
Playables:
-Poo: Robot
N - PK Thunder
F - PK Brainshock
U - PK Farewell
D - Mirror - Counters an attack by transforming into the attacker and performing a pre-determined move.
FS - PK Star Storm
Forward Smash - Sword of Kings
-Flint: Pig Mask
-The Masked Man: Unused Giygas model
N - PK Love - PK Love graphic attack shot from Masked Man's gun
F - Shield Killer - A swift dashing slash forward. Heavy damage to Shields
U - Jetpack
D - Lightning Strike
FS - The Final Needle - Pulls the needle and an eruption of fire bursts from the Masked Man's location, followed by a rain of fiery meteors.
-Porky (Smaller spider tank): Old Porky
N - Stinky Gas
F - Porky Bot
U - Hover
D - Powerbolt
FS - The Almighty Idiot - Porky summons Giygas. The player controls an invisible point slowly around the arena that is the epicenter of Giygas' incomprehensible attack.
Assist Trophies:
-Starman - Reflects projectiles and fires PK Beams
-New-age Retro Hippie
-Kumatora - Performs PK Ground around herself
-Fassad - Flies around the arena blowing his trumpets randomly. Occasionally upgrades to that multi-trumpet version.
Story Enemies:
-Starman
-Starman Deluxe
-Pigmask
-Terrifying Pigmask
-Pig Tank
Story Bosses:
-Master Belch
-Giygas
-The Ultimate Chimera (Unbeatable)
-Old Porky (Rehash)
Stages:
-The Devil's Machine
-Fourside / Moonside - Fourside Stage occasionally becoming the bizarre Moonside. Destroying the Mani Mani statue reverts it back.
-Saturn Valley - Copious Mr. Saturn drops.
Fire Emblem
Playables:
-Lyn: Nomad gear
-The Black Knight (Ike Clone? OR just an Alternate Costume for Ike)
-Bring back Roy with tweaked moveset
-Nergal: Unmasked
N - Luna
F - Nosferatu
U - Gespenst
D - Flux
FS - Ereshkigal
-Any mage, shaman, monk, etc.: Upgraded
-Any non-sword Knight or General: Upgraded
-Any thief or assassin character: Upgraded
-Any villain (Preferably magic related like Nergal)
Assist Trophies:
-So many characters, just pick 2 popular ones of differing classes
Items:
-Devil Axe - Does high damage, but has as high chance of doing high damage and knockback to the USER instead.
-Magic Book
Story Enemies:
-Knight
-Soldier
-Shaman/Mage
-Beroc (or whatever those animal guys are called)
-Monsters I can't think of
Story Bosses:
-Ashnard
-Medeus
-Zephiel
Golden Sun
Playables:
-Isaac: Adult
N - Move - Charging it increases the range, but decreases the duration. Hand becomes larger during FS
F - Cutting Edge - Becomes Plume Edge during FS
U - Death Plunge - Becomes Death Leap during FS
D - Planet Diver - Becomes Planetary during FS
FS - Djinn Set - All Specials get powered up.
-Matthew
-Sveta
-Saturos or Menardi
-Chalis
-Arcanus: Alex
Assist Trophies:
-Dijinn
-Some sort of awesome summoned monster
Story Bosses:
-Saturos and Menardi
-Fusion Dragon
-Doom Dragon
Stages:
-Any Lighthouse
Kid Icarus
Playables:
-Medusa
-Eggplant Wizard (Joke character)
Assist Trophies:
-The Reaper
-Magnus
Story Enemies:
-Shemum
-Putt
-The Reaper
Story Bosses:
-Dark Lord Gaol
-Orcos
Third Party
Playables:
-Snake: Naked Snake OR Old Snake
-Sonic: Classic
-Knuckles: Robot Knuckles OR Knuckles with a hat
-Megaman: No Helmet or all Human
-Zero: Megaman Zero
-Pacman: Mrs Pacman
-Lloyd Irving
-Simon or Trevor Belmot (I like Trevor better, Simon's classic though)
-Saki Amamiya (He's technically 3rd party, right? Maybe not)
-Marina: Calina
-Bomberman: Mighty
-Luso (FFTA2): Ramza Gear
Assist Trophies:
-Any Treasure character, Epsilon Eagle anyone?
-Dr. Robotnik
-Dracula: Teleports around the field, either shooting several fireball spreads or a series of Dark Hellfire
-Grant Danasty: Runs around throwing knives and axes. Can grip walls and cielings.
-Shanoa: Uses the Dominus to shoot up magic that rains down all at once.
-Protoman: Runs back and forth across the field while jumping, shooting, and deflecting projectiles.
-Dr. Wily
-Golden Silver
-Omega (Megaman Zero 3)
Stages:
-Field of Blossoms (MGS3)
-Castlevania
-Wily's Castle
-Pacman Stage
Items:
-Sonic Rings (Sonic)
-Eddie (Megaman)
-Holy Water(Castlevania)
"Other"
Playables:
-Little Mac (Punchout): SNES Mac
-Louie (Pikmin): No suit?
-Starfy (Legendary Starfy)
-Ray MK Whatever (Custom Robo)
-Tabuu (SSBB): Alloy
-Main Character (Animal Crossing): No Horn Hat
-Tom Nook (Animal Crossing): Business Suit
Assist Trophies:
-Glass Joe
-Bald Bull
(No other ideas yet)
Features:
-Worthwhile challenges in Event mode
-Better story mode with different branches of characters (so that you can't play as characters you haven't unlocked, but get teased with stuff you can unlock later). Everything converges by the end.
-Better ability to edit physics such as gravity and speed (more precise basically)
-Better wifi play
-Assist Trophy / Pokeball edit (basically enabling or disabling specific ones. Unlocked after getting every single one, certain rare ones excluded like Mew).
-Alternate Costumes for every character, OR an even MORE in-depth costume changing (picture the way Tekken does it).
I'm not even going to bother with my Story Mode ideas, but basically it involves Mewtwo being the main villain who's trying to give the Smash Ball to Giygas.
The fact that even a few of the things I mentioned are considered as speculation for the next game makes me happy enough.
Also I made up Snake Codecs for the Smash Bros project in the forum a while back. I still like these alot:
Porky Minch:
SNAKE: Woah, that little brat almost ran me over!
COLONEL: That's Porky Minch. He's Ness' nextdoor neighbor, but they couldn't be more opposite of each other. Porky is spoiled and rotten to the core.
SNAKE: HGRK! He drives that thing like a maniac! Dumb kid!
COLONEL: Porky doesn't have psychic abilities like Ness and his friends. Instead, he hides inside destructive machines to do his dirty work.
SNAKE: Grr... I'm gonna yank that brat out of there and beat some sense into him.
COLONEL: It won't be that easy, Snake. Although he has no psychic abilities of his own, he allies himself with an entity called Giygas... To put it bluntly, Giygas is evil incarnate, a force so strong it can engulf the universe.
SNAKE: That's ridiculous, Colonel. You expect me to believe that?
:The Colonel's side of the screen starts to get covered in red static:
SNAKE: Wha...? Colonel? Colonel!!
:The Colonel returns, but his face is distorted and wavy and red:
COLONEL: Snaaaaaaaaaaaaaake...
SNAKE: ...!!!
COLONEL: Snaaake... I'm... happy... it hurts...
Mewtwo:
SNAKE: Nn.. this thing is really creeping me out. It looks like an alien.
OTACON: You'd better be careful Snake. That's Mewtwo, one of the most powerful Pokemon ever.
SNAKE: His body doesn't look so tough... you sure about that, Otacon?
OTACON: Don't let his appearance deceive you Snake. His body may not seem powerful, but his psychic powers are off the scale.
SNAKE: Not another psychic...
OTACON: That's right, and he's not afraid to use his power. He's one of the most violent, hateful Pokemon in existence. I'd be careful around him, Snake.
SNAKE: ... but why the stupid name, Otacon? Why do they call him Mew "TWO"?
OTACON: Well...
SNAKE: Huh? What's the matter Otacon?
OTACON: ... Mewtwo is called the Genetic Pokemon. It was created in a lab as a clone of one of the most powerful and rare Pokemon, Mew. So far, only Mew's DNA has been confirmed to exist. Nobody has given a clear account of ever meeting Mew face to face.
SNAKE: ...
OTACON: Snake?...
SNAKE: Maybe he's not so hateful... maybe he just feels alone, and doesn't know how to cope with it...
OTACON: Snake...