Ok, my two cents worth now
The horizon, while I believe it was level when the photo was taken, looks off because of the angle of the river bank and the slope of the hill.
I agree with cropping the top a bit.
It does lack punch. However, if that is how it looked in real life in person, what is wrong with that? I have seen to many times where a photo is posted in a forum where they ask for others to edit, and people go way overboard with punching it up. Does it look good as a photo? Maybe. Does it reflect reality, no. So it depends on what you want, a good photo at any cost or do you want a photo that reflects reality?