This is an amazing shot. I'm not going to be able to find anything to suggest for improvement here. I think that your crop is perfect. The inclusion of that little strip of land at the bottom really enhances the vast skyscape. The tiny shadows of buildings there are what gives the viewer a sense of the dimension of the shot. The toning is very well done - the blue cast brings out the sun rays, and enhances the storm and turbulence.
This is so pretty, I have seen this effect so many times, the rays of light coming through the clouds and I never get tired of seeing it. This is a wonderful concept and the overall capture and crop is good. But the lighting is off a bit, seems there should be much more contrast in this shot and the white areas could pop more. I like the landscape on the bottom, are those houses? Really makes you realize just how small we really are at times. A 7
I think perhaps some work on the gradation of the mid-tones might help to bring out those rays of light a touch more. There's a slightly wide-angle feeling to it too - that curve of the horizon, the nearer clouds, which hasn't helped the impression of these clouds going on for ever: don;t know if the black one top of frame really helps that much - cropped out, and with therefore more contrast range to play with ... anyhow, good work.