To my eyes it looks a little overexposed. I think it somewhat lacks a subject. The composition is very nice I think, it has a nice 1/3 sky sort of thing going on, and a curve in the river for your eye to follow, but I find myself wishing there were something else in the photo to look at. Maybe if you were a few feet taller you could see more of the field, or if there were more of the background in view, or a little more detail in the river...
I don't think that you did anything wrong, but I will offer a humble opinion: Shooting this image during the very early or late part of the day would give you a much softer, more pleasing quality of light. The inherently lower contrast at dawn/dusk coupled with deeper hues in the skies would make this a completely different image.
