You are obviously very good at rendering! The bottom of the ribcage (top-most part) is about the only part of your drawing I can criticize, apart from the wonky fingers in the foreground :) It looks a bit flat, though I'm not a 100% sure why. Maybe wrapping the shading more around the shape, in some way?
The next thing is to do with personal taste, but I'll throw it out here: Maybe differ the amount of shading detail/focus between the part of the body that is in focus, and the rest. It may give it more depth, make it feel more alive and also make it rougher, in a good way.
Just something to try out :)