Beautiful scene. Great positioning to get river and valley in an appealing composition. I'd apply a bit of subtle HDR/Tone Mapping in sky and land to make it pop some more. Perhaps an inch off the top as Rian suggests but not too much! The sky is very dramatic.
Tad to much sky but great place and well done on working the light which seems to have not been the ideal time of day, yet rendered appealing enough to snap a great scene