Well first I'd like to ask, why do you have 3 different dither styles on the (farthest back portions of wing
) brown things? These brown things also lead me to notice the mish-mash of shading; you seem to have a lot of the lighting from the top left corner, but in some places, (the brown things, and the gold part on the bottom) the shading is way different--unify the lighting.
Next off, I'm assuming this is supposed to be metal? If so, some white highlights would do wonders.
Color-wise, I think you could easily cut the 31 to 16 with little to no information loss. You may also want to play around a bit with the hues if you want a glossy metal look (though it's okay right now if you are going for more of a matte yellow paint look).
But other than that, this looks okay so far; the shape is unique--very hi-tech and space-like. I'm looking forward to progress on this.
EDIT:
Got it down to 13...and started playing.....donno if this helps you much, but meh.
