Like in kerbal space program (which I really love) have the ability to send parts of space stations or other rockets to orbit a planet so you could build stations in space for things like refueling rockets and docking. But also have the ability for small rockets on your rocket like in kerbal where you can slightly change the rotation or direction of your rocket. And have more parts to build like hover planes and a air field and other things other than just rockets. And to have 3D added to the rockets or planets.