I see. Well, I quite like the look of this so far, but I don't like the way the grass just goes straight up to the base of the cliffs. It makes the cliffs that are over the grass look like they're floating or something, with such a huge gap in apparent saturation. Even a small transition would be nice. I sort of like the grass itself as is though. Nice and simple.
Also, the sandy color in your image doesn't seem to match any of the colors from the NES palette you've given...?