Hi!
Good job so far, i like the general design.
The way you have rendered indicates that you want it to be more "realisticly" as far as lighting goes (rather than cell shaded i mean), so i'm assuming that in my crit.
I would think more about the lighting, as the values are pretty similar throughout the piece.
The shadows are very subtle, you could easily make the forms "pop" more by darkening the cast shadows. For example, look at the legs, the similar value where the legs overlap makes them seem almost like they're stuck together in the knee.
Try to select the figure by clicking ctrl+left mouse click on the thumnail in the layer (in photoshop, (works in other programs too), and select a fitting shadow color thats darker than the ones you have used, and use a big soft round brush to "airbrush" in a stronger shadow around the forms, especially on the oposite side of where you want the main light source to come from. Also, try to select areas where cast shadows will fall, like under the arm and under the overlapping knee, and fill inn a stronger cast shadow.
This should make the forms seem more 3-dimensional.
I hope this helps!
