Even though KSP is an absolute amazing game, I would (at this stage) like to see a greater hand in the research aspects. The ability to actually design a rocket and its capabilities would be excellent, I think. To decide what kind of fuel flow versus power output versus price versus fail rate. This could be for many of the modules. Command modules with greater battery life at a cost of propellant or price tag. Construction materials that question price over durability or even the number of hard points for adding other modules. If a player doesn't want to construct their own KSP produced products, they could always default to the many companies eager to peddle their wares to them.