I agree with you on the BG, it adds alot to the image. Nice gliding-down pose. The far wing is on the bright side, perhaps you could tone it down a bit.
I love it. You really get a sense of movement with the pose and I like the fanned tail. The whites look okay on my monitor and there's plenty of detail in the feathers. I like the background a lot. Excellent work.
I like the BG and the light shining through the near wing and tail feathers. The bird looks very sharp. Far wing looks a little hot on my laptop monitor, and far wing position could be a little better.