As usual, very nice work.
I'm curious as how your brush settigns are. Hoe do you achieve that quill-like look? Meaning the interrupted strokes and irregular thickness. My guess is that your brush tip is something like a rectangle and is set to rotate, which would achieve the variation in thickness, but I'm not sure how you got the interruption in the lines... unless you just lift the tip of your stylus.
Also, so you have problems keeping yourself from putting too much detail into your mountains? Because I frequently get lost in drawing too many details but find it hard to stay away from it. In my opinion your mountains contain just the right amount of detail, without having too much.