Strong lighting from about the position of the observer would explain the shadows and highlighting on her and the droid in the right of the image, but the left droid seems to be a little out of synch with the direction of the lighting.
Minor anatomical criticism... Jupiter's hips are in a fairly neutral position with regard to tilting or twisting, so her left leg is a bit disproportionately long.
Significant anatomical criticism... positioned as it is, her left hand appears to have been broken and twisted, since her thumb and palm are visible. If she's not wounded, her arm in that position would not have the thumb visible, and if her arm is twisted to show the palm, her thumb should be on the other side of the palm.
Well I can surely say that it's not a matter of being harsh since I don't normally produce art as fast or regularly as say Jolly Jack or the fellow who does the web comic Sinfest every single day. I've had no real "formal" teachings in producing art works and just do what looks good to me. However, even though I don't think I could promise noticeable improvement, I still am very interested in what a viewer thinks when they look at my art. I may be happy and satisfied with my final products, but having an audience for feedback rounds it all out. After all, whether the critiques are good, bad, constructive, or whatever, people "looked" at my works. Critiques such as yours are pretty detailed and certainly give me something to think about so thanks very much.