It's pretty impressive image in my eyes, but I think there's not many stuff happen in the sky. I would crop about 1/3 in the sky area. I find the most awesome part of the pictures is the glorious mountain. Getting closer and stitching 6-10 images into one big panoramic of the mountain range might be a great idea. Adding a bit more contrast and a bit of burning and dodging can bring out more impact of the image. This is simply my opinion and I hope to see more great images from you. I'm sorry for my bad English since it's my 2nd language.