This jumped to mind for me too. Basically 5-10 unique elements per planet, arranged to give it an organicish feel, but the terrain sadly lacks much to explore.

This jumped to mind for me too. Basically 5-10 unique elements per planet, arranged to give it an organicish feel, but the terrain sadly lacks much to explore. The most interesting planets tend to be more forested or have extreme terrain features, but the patterns are still obvious.