as other mentionned, the lighting is too harsh... although a question of taste, I find black backgrounds highly un-appealing and is something I never aim for, I usually discard any shots that has flash falloff with a black background. I mention this because from your point "5" I am under the impression that you were aiming at having a black background.
the hind bottom part, you can see where you have stopped retouching right before the bristles, these hairy zones are always touchy to fix with the stack, but it is worth taking the time.
Last, I do not believe that you would really need 50 shots for this image and sometimes, I find it nicer not to have the full animal in sharp focus, but of course, again that is subjective.
For a dead animal, I would avoid showing parts that clearly gives away it is dead, like the curles legs, I would have concentrated on a portrait of the face. It makes the picture more appealing.
Martin