This is very plain in every possible aspect. Mass of the same grass, a few trees, a little peer and a few ruin doodads and some units which are way to big compared to other doodads placed here and there.
You need to work a lot more on your terraining, not that it is THAT bad, I have seen much worse, but this is not good by any means. Try and follow some of Bob27's advise and perhaps read a few of our terraining tutorials in the tutorial database.