Robbie,
I like the atmosphere you achieved. Panoramic composition is notoriously difficult, but you got that mainly right.
A couple of things I would do differently:
- I would probably get rid of the fence or at least give it a different, less contrasty/dark/harsh treatment
- I had the same idea as Peter, i.e., moving the birds to the right side; in contrast to his version, I would have them a bit more prominent, higher up in the sky, and a bit closer to the right edge - they would provide a nice compositional counterbalance to the tree
- One thing you can not improve in post processing though (except by cloning out), but could have been achieved at the moment of capture: the wire touches the bottom of the closest bale - a little separation goes a long way visually
Hope it helps.