You are not going to like this.
1:
Stop trying to make it something it isn't. If you want a picture of a banana, go and find a banana. Don't take pictures of a potato and then go heavy on the yellow in post.
2: It's a soft, beautiful, flat, grey morning. Try to capture what it
is, not what it isn't.
3: Cut out the bits that you don't want! Show the subject, not all that other stuff! I'd take out the rightmost 20%, the leftmost 10%, a tiny bit off the top, and a really tiny bit off the bottom, leaving me with the interesting rocks at centre right and left, the imteresting skyline, and the interesting water movement in the lower centre. (Best to do this in camera during
composition, but better late than never.)
4: Ignore the histogram! The histogram is a tool that can tell you what's going on in a picture. It is not, repeat NOT a guide to how to expose a shot in post. If you let the computer decide how much
light to have in a picture,according to the "ideal
rules", it looks like a picture made by a computer. Your eye should decide, and if that happens to leave the histogram unbalanced, we don't give a damn! Nature doesn't look at the histogram before it makes a new day, it just does it and leaves the
light to fall as it pleases.
5: Can you do anything about that terrible curved horizon? I doubt that it can be made straight, but at least try to tone it down a bit,
6: Experiment with a darker overall look, possibly quite a lot darker.
7: The colour balance in the first version looks about right. The second version ... well, I've seen those colours before, usually on a Sunday morning outside a hotel. Go back to the first one. That one is pretty good.
8: I told you you weren't going to like this!