Ok, i added more plants and trees. I made a custom leaves paint tube brush to add literary thousands of leaves. I think it look fairly good. I still have to finish that bare tree in the top right (at least you can see how I build one).

A few more shrubs here and there should finish it off. I'm thinking of popping a few flowers too. Not sure about that though. So what you think so far? Anything else I should add?