If you are worried about your characters, then try some full body pictures. You have a lot more room to make them look different. Personally, I tend to use ears and nose shape to make them seem different.

I haven't quite learned anatomy of full body yet.... I have dozens of full body attempts that I trash.

That's unfortunate =/
How have you been doing full bodies so far if you don't mind me asking?

I try to do that weird spine thing that all the pros talk about. From there I draw lines out from the spine to form when the shoulders/hips might be. Somewhere between there drawing the general body mass I changed the angles of the body numberous times and become frustrated. At which point I stamp the paper with the forehead of failure.

Hrm. Well that is similar to what I do. But I don't draw the lines straight from the spine, but make a box for the chest and a triangle for the hips. It makes it more proportionally easier. Plus, the main use (for me at least) of the skeleton is to have the pose ready, and to get proportions correct.

Yet you have probably heard this before. So what I am going to say, is be willing to overlook little details. If you see them too much, its ALL you are going to see and it will look much worse because of it. Trust me, most people don't see the mistakes that you do. It surprises me how much you can actually get away with 0_o