If the game will look a third as well as on the trailer visualization, I'll buy it without thinking (who am I lying to, I'll buy it anyway). One thing though: I hope the modding capability and freedom won't be diminished.
If KSP is a great game by itself, mods make it a literal order of magnitude better - a huge amount of solid fan work was done to expand every imaginable aspect of KSP. And I mean it: among many things, mods give you many more realistic and unrealistic building blocks, life support management, communication networks including speed of light delay, trajectory planning, UI/UX improvements, graphics improvements, orbital assembly, working space telescopes, realistic aerodynamics model (including supersonic physics), n-body simulation and non-symmetric gravity fields,... I don't think there's another game where so much of such highly skilled effort was spent for free to make it deeper.
I really hope they won't do anything that would make this depth of modding impossible.