i think the concept and the pose is great, and i love what ur giving
but i would like to give some small criticism that i hope will help u
the colors are not going good together, i think u should use the same (or similar palette) colors to use for shadow and change the layer settings to overlay.
and i think u should focus on anatomy, the pose is really good, but i think u should pay attention to proportion and how thick and thin certain body parts are.
but overall, i really love this piece