The first thing that popped in my mind is what rlm posted. Although I would have tightened up the illumination around the girl even more.
I second mcgeedigitals contrast suggestion. Although the level of contrast can be a preference thing I would definately use some of it. I think you are on a great track with what you have Nathan. Good work.
I'd say a very slight increase on the cloud contrast. Leave the horizon as is. I love this photo. Maybe a bit on the goofy side, but I like the few stalks of wheat in front of the piano and almost her. I didn't see where you may stated what the photo is for? Someone suggested as a movie poster, leaving the field as is at the bottom for some text. Good idea in that case. Rick Lee, that's pretty cool what you did there.