Feedback you ask for, hmm.. sadly I'm seeing a few things that are dragging this one down.

1st. Her hand it's just has a awkward painful grip on that disc. I'd try to make it more lean/flexible in the hand wrist joints not so stretched. Also I see I'm finding the disc a little to flat, give it a little feel to perspective and to her hand then to how she is holding it.

2nd. Her ear, you seem to do this quite a bit it's a small detail but if you forget about them it makes the person distorted looking. It's not aligned to her face quite right and it's slightly below her eye-line just by a notch nothing major their. Just remember to keep your ears in align to the face when you draw them in. Having it like that if she moved her head back her ears would stick out backward. I hope you get that fixed it really brings down alot of your good pictures from being great!

3rd. Her neck lines are spaced a bit odd. Looks like you tried to show some twist in her neck but it's slightly incorrect I believe. The one on her left should be where her side jaw is at about but a slight bit on the inside. The one on the right should almost not be seen, I would've showed a bent cringe their almost. Because of the oddness their it appears her head is floating and not connected to her body.. sorry to say that.. Also having the neck lines that far apart on a female also makes her very muscular looking but it doesn't go with her lower body if you ask me.

Here's an update: