Badger is right, this certainly has potential. It's quite daring to try a landscape like this, I appreciate that. I have some suggestions: increase the displacement in the fractal on which the stone population sits, so the stones spread out more in height (for a rougher fall). You should also move the whole fall a bit towards the rock wall, so you loose the straight edge where you look under the fall. It may also be possible to make the fall area 'rounder', but that's up to you, can't help you with that.
Then the snow. Try a displacement intersection and see what happens. You might loose the fall area, then it won't work. Otherwise, restrict the snow to lesser slopes, so it's not on the ceiling of the caves (which are nice). You could also try to reduce the intial fine roughness of the terrain, then add snow on lesser slopes and add some minor rough displacement where there's no snow, but that takes some fiddling with masks...
And then I'd at least add some patches of color in the valley, like snow or bushes, for diversity.