Personally I think that OC Arctic DM would be better if the Ice wasn't one flat layer with piles of god knows what ontop.
All of this terrain talk is making me feel like completing my old MotE app that I started immediately after my first one(last year) and still isn't done.
Anyways, to effectively emulate terrain, you need to keep revising it. Think of dwarf fortress- the world goes through many many changes, regions are rejected and such. It doesn't keep every last thing that's produced, it keeps going till it has a good one. Terrain is very similar, which is why I've continued to improve on my design since day 1.