Well, it looks beautiful, man. Well, it would, but the face bothers me a lot. It looks like the chin and face outline tilt at an angle that the other facial features (eyes, nose, mouth, etc) don't, and the ears seem like they should be further back on the head.
The hair doesn't bother me at all, but I'm probably not as experienced as Charry or Vishal.
The elbow looks like it has one more joint than it should (the curves around that point are all wrong) and the fingers definitely do look off, tho I didn't even notice the arm the first time I looked at it because the face->chest->back->hip->thigh attracted all my attention away from the arm.
And I didn't notice it at first, but like they said, the thighs appear too big for the width of the hip.
Also, with the position of the shoulder where it's at, she looks very tense because she's obviously using her muscles to lift up her shoulders. This contrasts with the more relaxed feel of the rest of the piece. Relaxed shoulders are usually harder to draw IMO and usually hang a lot lower (which IMO is what makes them more difficult to draw).
And I just noticed the nose, which seems to have one nostril hidden, which would imply a viewpoint contradictory to that established by the rest of the place. Also, the rings on her back are inconsistently drawn. Several of them look mangled / misshaped.
Other than these things that bothered me, this looks like a really beautiful piece. In terms of light and shading, I really can't offer any advice.
-SG7 ( :) )