I think it's eEXTREMELY good! :P I do agree with the thought of a muddy or wet look just above the water line. My only personal suggestion is that the right side could use a little more value contrast for balance with the tree on the left. Maybe make a bush with black branches or dark leaves behind the other tree, so that you only see bits of it. And (just my opinion) a couple of flying bugs or birds, or a bunny in the grass or something would add a lot of life and interest. That's just personal preference, though. I like landscapes that look lived-in. :)