It looks like your sculpting on a high poly model from the very beginning. I would start with very basic shapes, at a low poly level, and then go up. Otherwise it starts to look mushy. It lacks a lot of structure.
you're at point where you are far along enough where you can call this done, and move on to the next one. For your next piece, slow down, use some of the tools that come with in zbrush for reference, like the Ryan kingslien anatomy model. I would sculpt in a neutral pose first with symmetry on, it will make things way easier in the beginning, once you are done with the model, then you can pose in zbrush or rig it outside of zbrush. Your rendering could use some improvement as well, have you looked into Raf Grassetis videos at all? that dude is wealth of knowledge