I might consider a modest crop down from the top to move the bird higher in the frame. If you have more of the perch below, that might allow the repositioning without the crop going too square.
He is very sharp, right on the verge of oversharpened on my monitor. The exposure looks good, maybe just a bit hot on the yellows in a couple of places such as the throat. Did you need to pull back the exposure at all?
In looking at the image some more, I wonder if there isn't a bit of a green color cast?
Will be interesting to see what others say, perhaps just my perception.
I echo what Randy has to say on the top to be cropped . My guess is that this can substantially brighter !! The yellows do look a bit hot . But on the whole , the image is wonderful .