You've definitely got this technique down, Steve! If I might make a few small suggestions: It's always nice to have a little more room on the end of the frame for the bird to (potentially) fly into (left side in this case) so a little more canvas on that end wouldn't hurt. Also, although I don't mind the lightest gray spots in the image, the ones right around his beak might be worth cloning out so it separates the bird from his BG a little more.
This is really a cool technique, though...I'm going to have to give it a try!