I think those mountains look great on the Gimp version.

I love Ascension's overall style created in these tuts but I've never been a real fan of the mountains in them, which most of the time to me look more like rolling clouds or a beautiful nebula than mountains, which is why I usually comment when people improve (in my eyes) upon the usual mountain results when they follow this tutorial.

I would imagine that at the distance your map is drawn the mountains would maybe not appear that craggy, dunno, I think they look cool though.