Nice tonal contrasts Denise. Try doing a filter/blur/surface blur and see if that gets rid of any of your remaining noise. I'd also look at either doing a dark vignette all the way around the image or removing the two dark corners at the top.
I think I would remove the dark corners Can also play around the the clouds on the right and play around with contrasts.
For clouds I like making a selection (large) feathering 75 pixels and darkening, increasing contrast etc. Then I make a smaller selection inside the previous and do the same but feather less, usually lees contrast increase. Works sometimes :)