I'm just going to start off this post by saying that I'm a big fan of you're 'anime' style heads.
For this head, though...
The color scheme isn't really my favorite. I don't know where you got the idea to put a
really dark turquoise with a purple. I think that if you changed a bit of the colors and
shading around, it would be wonderful. Also, the eyes kind of stand out, because it's the
only white in the head. I don't know if you were trying to get that effect, but either
way, it worked.