I like this shot a bunch. If it was in the wild, you are really - and I mean really - fortunate. If you area asking me to be entirely picky (which I think you are), the one thing that bothers me about the image is that there is darkening at the bottom of the frame. I am assuming that it was taken in a blind, and that is what we are seeing? As the wolf's feet are already a bit cut, it seems impossible to crop it out.
Over-all? A very very nice shot - and if this was in the wild, I know how fortunate you are just to have experienced it, much less having gotten the photo.