I suggest or would (very much) like to see procedurally generated planets. So that the player is able to keep exploring endlessly on different planets in/with different positions (orbits).
My second suggestion is to add adequate objects such as (moving) volcanoes and cryovolcanoes. I really like the easter eggs, but this will be a more frequent special features of a planet or moon.
I would like to know how/if this is do-able in KSP, and what does the community think about this? (have I spelled everything correctly? )
Apart from that: A lot of real life planets have unique features that make them special such as Tritons young surface and Titans cryovolcanoes. Some moons even have a very thin atmosphere and/or retrograde orbit. That is what I like about space, and I think Kerbal Space Program has this too but at smaller scale. Yet I love it.