To me, it looks like there is too many levels of shadows causing the details to be hard to pick out. I tried to take the shadows so I could examine the image better.
I noticed the back leg was strange looking and the foot was pointing backwards. The foot pointing backwards works for a standing pose but I think it might be weird when you have to shift the foot forward when shifting into a walking animation. I also make the leg a bit thicker and shifted it forward a bit to try and make it less bent.
From there, I added some shadows back in. I noticed that your version had a lot of 1 pixel shadows around the vest. To me, the shadows made it look like the vest was floating around the person instead of being worn. You could definitely use more shadows then what I used. Just make sure the character is still readable.