Holy crap Goemar is creating stuff

[StarSock64]

I'd say you should focus more on your lightsource. Since they're gonna be from the same game they should probably have the same lightsource, also. You have all sorts of banding, try to get rid of that and think more in terms of how light would hit the shapes. I know that's a bit of an "easier said than done," especially for beginners, but experiment a little. The simpler shapes, like the circular parts, would probably be a good place to start, since there are so many examples of shading on circles. That sort of dark yellow shade kind of reminds me of old Nickelodeon game sprites or something so you might want to look into hueshifting that somehow. If I can find the time to make an edit I'll do so!