Needs a development/research tree. Should start with stations like sky lab, then unlock new parts or abilities on older parts (Like a modular design tech that lets you begin connecting things) and you end up with flying trashcans similar to Mir, then ISS, and onwards to future tech, things that are just concepts atm. Could have them increase your funding, due to companies/agencies wanting to use your station for research. Or even your research speed into certain things.