Sprites are cute and versatile, very good. I think a simple plot idea is good enough provided the game play is solid and fun. It looks like you're going for something like Contra or Metroid with the way you can aim all around while moving. What kind of weapons will you feature? And are there any interesting platform/puzzle mechanics that would set this apart from pre-existing NES titles?
Also, just out of personal curiosity, what are you making this in? Game Maker? Unity? SDL? Personally, I'd go with SDL, since that works on the widest variety of platforms, and a game like this would certainly be popular on open-source platforms like Dingoo and Pandora, the latter of which doesn't have enough retro-style games. If you're using SDL 1.2, I could also help with debugging and whatnot, as that's what I use myself.
[EDIT] I just noticed you're using SDL. I didn't see that under the video at first. XD
Also, just out of personal curiosity, what are you making this in? Game Maker? Unity? SDL? Personally, I'd go with SDL, since that works on the widest variety of platforms, and a game like this would certainly be popular on open-source platforms like Dingoo and Pandora, the latter of which doesn't have enough retro-style games. If you're using SDL 1.2, I could also help with debugging and whatnot, as that's what I use myself.
[EDIT] I just noticed you're using SDL. I didn't see that under the video at first. XD