another small hint:
smallest circle and paint somewater vein with shift + mouse pressed. also remeber real mountains have no curves, instead hard edges.
Sometimes I use also the flatten tool to create a kind of plattform(Anden). Also a pretty usefull tool is the ramp to create good change overs.
The best is to look on some pictures of a mountain.
Hope this helps in any kind
My dream is to develope games, which makes fun when I create it and fun when other people play it.