Here's the huge rundown everyone thinks, I think
I think that your characters are a bit too thin. The arms, especially, are a bit small in width. Now, realism shouldn't be a huge factor in drawing things (HELL HUMAN BIRDS DONT EXIST), however I still think the structure of the body needs work. An easy way to start grasping a human structure is to find a position that is extremely easy to draw. A lot of your art consists of the person looking to the right, or their left. This can be a start of where you can figure out what looks good. If you're going for a not so realistic approach to the body, then instead try to define a line between the two.
This area in question is what needs work:

Yellow: Over here could use more width.
Red: Sure, you can say that's the feathers, however it is very jagged nonetheless. You should get to work on figuring out how to make an initial straight line, then add the fur/feathers. This way the arm can be more prominent than the fur itself in shape.
Green: Hands are hard and you can learn the rest.
Blue: Like Tesla said the hips/stomach is not definitive. Sure, not every girl is perfect, however the hip here is very straight. It could use some rounding. Also, I'm not the one to say but breasts kinda slope downward at first then round at the bottom.
http://www.youtube.com/watch?v=lnqCXe14PWA&t=0m19s