Hands are pretty akward to draw, especially with natural gestures. To help, think of the muscles underneath the hand, and try and show them working. In a relaxed stance, give little tension et cetera. The Pokeball could have a neat DEATH GRIP which shows major flexing beneath the flesh.

Also, don't shade everything you draw with pure black. Right now, you need practice, and hiding portions of your drawings won't help you. Once you get better, experiment with high contrast shading like that.