Design is pretty cool, although a helmet would have been both wise and cool to wear. I like the shadow design changes (white circles).
Worst thing that I see: Right arm, just looks wrong in that position with the hand like that, uncomfortable and doesn't look well foreshortened. You should check that out.
Another thing I don't see well is the specular white at the hair, I think (just an opinion here) that you might have wanted to add a lighter saturated colour in combination there to match with white, and some halation at the other side (with the light saturated colour) would have been cool to see also.
But overall looks nice and the final touches are correctly done. Nice job !