Sprite looks great so far :D
Some critique would be to make the shading on the sprite on the right a little more uniform, since right now it's a weird mix of simplistic BW style and some kind of heavy-shaded style. An example of the conflict is comparing how the cape and head areas are shaded, (being super simplistic with a single shade color), and the shirt and pants, which have multiple layers of shaded colors.
In my opinion, I'd go with using a BW style, so reducing the amount of shade colors there are on the shirt and pants would do wonders with fitting it into a fangame!