@littlecannon: I have to correct myself, I didn't use a painted shader but simple powerfractals (ridges, high contrast, high roughness, with the X=15, Y=1, Z=1), as the blending shader for all 5 populations. They were further restricted to the same small area of 300x100 meters or so, but the heights of the objects themselves were different per population, between 20 and 30 meters, to lift them. And (very important) restrict the rotation to 0-10 degrees. So it's very simple actually.
---Dune
