I don't like the layout of the level. the thing looks great, but it's basically a flat plane with mountains around it. there's just two levels of height, plus one thin river...

http://www.bildarchiv-boden.de/kula/kg/Bach-Neuffen-Fruehjahr-klaresWasser.jpg
I think you should add a dirt texture in some places. the green's too consistent.
there should be a slower transition (at least in some places) between (way too) rocky mountains and grass plane...

it looks amazing though!
Micha


~"I never let school interfere with my education"~
-Mark Twain