M&L Jammin'

[Iocus]

I think your contrast is much too low (particularly talking about the M&L3 Mr. Saturn.)
Left is mine.
Most of your colors are meant to be transitional, but you need a color that greatly difference from your base hue to define shapes, such as the nose, or the border between the feet and the body.

I'm not sure if mine is exactly in style (haven't played this game), but the features are more distinguishable, as with Mario.