This looks very good! Good composition and clouds
I'm glad you didn't make the foreground too 'busy' so the attention keeps on the cloud.
The surfacing is very good also.
There are some minor things I'd like to see improved. The water is a bit rough to my taste, however I can easily imagine it is very windy there, but the wavescale is a tad too big I think compared to the stones. The clouds and sunglow effect are great
Maybe you can lighten up the shadows in the cloud a bit to show a little bit more definition.
If possible: render this BIGGER
Beautiful work!
Martin