In my opinion, these two shots require different print sizes. The first, to my eye, would look best printed large, say 24 to 36 inches or greater, given its "contrast frequency" (for lack of a better term)- it needs to breath, so to speak. I suspect its aggressive tones will not fight one another on a large canvas.
I prefer the second, at least at these small sizes. The contrast in the sky seems more muted with respect to the foreground, providing a soothing, "yin/yang" effect. It would perhaps look best in the 15-20 inch range.