I'm really wondering what it'll do graphics-wise, how it'll differ from the original game and what new stuff it will have to offer.
I assume there will be a strong focus on station and base building, the question is whether it'll be different enough to warrant a new game or if they couldn't have done it as DLC.
Space stations, surface bases and rovers have been notoriously useless in KSP, so I do hope they'll have a decent idea to change that.
Will be interesting to see if this is a new engine and what they'll do about Mod-Support.
What features would you like to have?
I personally would like to see life support mechanics, ISRU being expanded to be able to build stuff on different planets/in orbit and some more options in crew management.
A bit more variety and customization with parts would be nice, too. I never understood why KSP doesn't just have tanks in different shapes and the player can then choose what they contain - ie: you have 1 MK2 fuselage and you can choose whether it's a LF/LOx tank, a liquid fuel tank or a Monoprop tank, instead of having 3 different tanks with the same shape but different contents clog up the parts menu.
Oftentimes, I'd love to use a version of this tank:
With only liquid fuel, but I have to choose and either use a different tank altogether (which usually doesn't look as nice) or I just ditch the useless oxidizer (which has a shitty form-factor, considering I am wasting "half the part" being empty.