Okay!

First thing's first: the shape. Forget the shading until you get the shape correct.



The neckline could curve a bit more...it's too stiff feeling to me.

The other biggest problem I see is the hem of the top looks like it's not rounded enough...it's awkwardly sitting up on the hip on our right..needs to come down a pixel or two.

I feel the sleeves should curve in the opposite direction they currently art. Right now the ends are lowered than the middle and I feel it should be the opposite

Here is a pretty good ref for shape: