Welcome to the club.... heh.
Your scene setup is very, very good, but I have some suggestions for you:
Sun position: I would have changed it so the light is shining from one of the sides. I know this may not make any sense at all and look more like a personal taste, but I know it's very hard to get good results with this type of lightning.
Background mountains: They need some work on the textures. But I also think that another sun position would make them look a lot better. (More shadows and stuff like that).
Grass and stones: Need some work on the textures to give more variation like said earlier.
I hope you don't think that I don't like it, but if you gave this a try I would love to see a update cause I think this one has some great potential.
Like I said: the scene setup is very good. I like it very much. Good luck.