cnc: the face portion looks weird when i map it. to a sphere. i'd play with moving the eye location up and in. but its so hard to tell with only that much shaded.
n-junk: just because you are making a purple head doesn't mean your extreme highlights and shadows have to be in the same hue(?) don't be afraid to pull your slider down into the blues for shadows.
more and junk: stop rushing your shading :3 your not going to get the pop you got around the eyes if you dont take into consideration your light sources