I think you need to break up the nearest strata (simple shape to control area + PF), and try to get a lot of shrub (or fake rocks) under the trees, so that these frontal flat areas aren't so smooth and strata-like. And perhaps hit the cloud seed a couple more times for another shadow distribution. The dark spot is a bit obtrusive, IMHO.
I like the one or two fallen trees.
Oh, perhaps also remove the trees from the further higher altitudes.