Forest looks very nice to me. It's thick but subtle in a natural way, if that makes any sense. It's dense but it doesn't stand out or seem out of place. It might be worth changing one or two things, but that's just my opinion.

For example, those mountains (to me) are perfect for one or two very thin rivers to flow from them down into the lake. As for the forest itself, I really like the way it looks but the borders of it seem too consistent. By that I mean, it might be worth having the forest density gradually thin out a bit as it reaches the ends.