Your line quality is very good. I would work a bit more on an inside-out basis, meaning go for the inner forms first (chest, hips, etc.) with simple shapes, then build from there.
Have you ever read Stanchfield? He was a Disney art guy for a long time and was part of the training for Mark Henn, Glen Keane, etc. A couple of volumes of his handouts for the Disney guys are available, and they really helped me out. They're more about gesture, but they are really good. If you can't find them at a library, or whatever, Josh Cotton has 'em (I'm borrowing the first volume from him), so ask him.