Quote: "and maybe a re-texture of the upward stretched cliffs"
It is not so much the texture you can use a 4096 x 4096 texture and it will still look odd.It is the way textures are assigned to polygon that is cause the problems.
In particular cliffs being higher polygon which results in more dense polygons which results in the odd look, what really needed is the engine needs to calculate the amount of polygons in a cluster lets say 400 x 400 units and then apply texture to that whole 400 x 400 unit.
It seems the engine is calculation at 100 x 100 units polygon clusters, it is evident with the repeating pattern on flat terrain.It also means however the larger these blocks the lager the texture will need to be to stop it from looking pixelated, down side is more GPU memory will be consumed as a direct results.
The other issue is the shader it self, you could theoretically have texture scaling in it which allows smaller version of the texture to tile better divide the texture by 4 in the same space, meaning you can have the same end result with low and medium settings.
I could be entirely wrong :p
