This looks very nice indeed Dune! It's a pleasant composition you have there. The polders in the distance with the islands running through them give a good sense of depth and scale of the environment.
I hope you'll work a bit more on the foreground however. Perhaps have the pathways worn down a bit more to the point where they slope down a tiny bit in the center as well as having a smoother surface. That and have some smaller weed-like plants (shorter than the grass) bordering the edge of the path for a better blend. It's a bit too abrupt right now. That is unless they are meant to be footpaths of course.
Also maybe experiment with adding a few more populations to add things like small pebbles, fallen leaves, and general "debris of nature" of that sort. Don't go too far with it though, right now the composition has a peaceful, minimalistic look to it. It would be a shame to lose that.
I must say that I really like the darkness of the trees (as well as the houses). It makes it more realistic in the photographical sense. I wouldn't brighten them up if I were you.
If you were to take a single photograph of a similar scene, under similar lighting conditions, you would never be able to capture a wide enough dynamic range to correctly expose both the brightness of the clouds/sky and the darkness of tree shadows. A choice has to be made as to which parts you want to expose properly. In sunny lighting conditions it's always a sacrifice you have to make. The power we CG artists have been granted enables us to bypass such limitations.
'Great power comes with great responsibility' as the saying goes and often times that power is exploited with the unfortunate result of unrealistic imagery. I think you've done really well here!
