I like the procedural texture you made.
It almost looks like sand dunes, but
something makes it look small and
not like few mile area of dunes.
Which texture you tweaked for it?
Try making the X and Y layout of the texture on the material Bigger so the stratas of rock are smalller giving the impression the area is much bigger. A sky would help and maybe lower the camera angle. MAybe a misty fog, some water, some trees and rock and you would have a very nice landscape. Very nice job on the model of the terrain though