Spark's Sprites

[SparkMouse]

Specifics for line work: most of it. Hell, it looks like you used the circle tool for the top of Baron's hat. I'm not saying restart, I'm saying look at some official sprites, look at the edges and get some inspiration of how to smooth it out.

"Most of it" is even less vague. What specific parts of which specific characters are you talking about? Why would it matter if I used the circle tool for the top of Baron's hat when the top of his hat is supposed to be a circle?
There aren't "official sprites" of anything Studio Ghibli. None of the movies got their own games, and the only game which Studio Ghibli had a hand in used 3D models (Ni no Kuni).

As for the scale. That's a terrible excuse. You have Kiki and Ponyo as good general references to go by. Totoroko is far too big. And when did the Baron become full size? Kiki should have to kneel down to look him in the eye.

How is it a terrible excuse? Olimar is the size of a quarter and Pikmin the size of dimes, and yet in Brawl, Olimar is the same height as Kirby (8 inches tall) and Jigglypuff (1'8" tall). Dedede is about 1'4" and yet appears to be at least three times taller than Jigglypuff, who canonically is 4 inches taller than him.
When Baron and Haru were in the Kingdom of Cats, Baron was very noticeably taller than Haru because Haru was scaled down. I just did the opposite and scaled him up because it made the most sense for having him playable.
And I even specifically said that I knew Totoroko was too big.

The blue Totoro needs to be redone since I made it a lot bigger than it should've been (I noticed this after rewatching the movie a few weeks ago).

Having things properly to scale is less important than having things at a playable scale.