Looks pretty good to me. The cardinal is sharp. The head angle is border line, but it still
works for me (my personal rule is the HA should at least be horizontal the camera plane
vs the HA should have at least a slight head turn).
I also like the branch and leaves.
On my monitor it does seem a little dark though. Maybe bring up the exposure on the
cardinal only, just a smidgeon.
Good pose with a nice green clean BG. Looks as though the bird needs a little more sharpening. If you have a little more room on the bottom, I would give those tootsies a little more space.
A little cleanup needed on the cloning, but that can be done. I'd go ahead and crop out the leaves on the right -- not enough of them to contribute much. They would have been OK if the original frame had included more at the bottom. If time, I try to bracket composition, especially with a zoom lens.
It does look a little underexposed and flat. Try checking the histogram and bringing up the whites.
Would love to see more! This is a bird I never see!