The enemy variation in this mod is absolutely amazing! It got me thinking, actually, about the possibility of a mod packed with planetary variations instead.
As it is now, some planets have notable variations (forests have different types of trees, things like that), but for the most part a lot of the planets look rather identical overall. I think this could be solved with more changes such as grass color differences (yellow-green grass, blue-green grass, everything in between), more grass sprite differences, multiple types and textures of dirt, even more stone types, etc. Not exactly the ridiculous colorful planets of the original Koala versions, but something new enough to not make planets as stale as they currently are.
Heck, this could even extend to backgrounds, like some planets having very notable volcanos or other landmarks (random cities, perhaps?) in the distance. But I might be getting ahead of myself. What do you guys think?