why does the sun have a black outer circle?
Henry, I think the lighting isn't quite there yet and the water looks noisy. I would like to give you a tip for the lighting of the sky, but I'm not sure how to express what's "not there yet". You probably need a bit more haze and glow, and the bluesky should be a a tad less violet, but overall I'm not sure and you just have to try it out.
Check out
this old image of mine. I'm not saying yours has to look like this, but take it as a color reference for what I am talking about.
Cheers,
Frank