Hearing that colonies can be built virtually anywhere on any planet with any parts you like in any configuration along with automatic resupply routes created is really awesome. A little logistics and base-building added into the game. Those are a couple of my other favorite genres, so I'm really excited for that! And getting multiplayer online would be incredible, Building bases with friends!
I really hope multiplayer is p2p self-hosted. Reduces costs for PD since they won't have to maintain a bunch of multiplayer servers and it guarantees that KSP 2 multiplayer will always be available even if something were to happen and KSP 2 maintenance stops (God forbid)