If it were mine I'd also increase the contrast on the small hills with a bit more highlights on the tops of them. I'd also burn in the top slightly, not obviously but slighty. As I said this picture has great potential and I'd play with it a lot. You have an Ansel Adams quality picture to work with
Have you considered cropping down the top to the the first puffy cloud to get the horizon line from being dead center in the picture and also straightening the horizon as well. This picture has great potential.