I'm thinking that rather than cropping I would play with the features of the water to bring out the colors in it. There are blue, brown and green striations in the water that would make a nice counterpoint to the boldness of the shore scene. There's also a hint of atmospheric color near the horizon. It all depends on what can be done with color and contrast without blowing out the whites of the clouds.
I like the rocky shore on the left. Very nice detail in the bank. I would have considered cropping off about 1/5 or 1/4 of the picture on the right side. That would bring our attention more to the tree and the rocky shore. Just a thought. To keep the same proportions and equal amount might be taken from the top. But, it might now work either. (see how indecisive I am?) :)
