right now starships are just a status symbol, if you have them then your colony is rich and everyone knows it. my idea is for starships to act as space warships. colonies would use these ships to establish zones of control on the my colony grid map. any colony in that zone will have to pay tariffs when using their gbt, and if they don't they can be sanctioned. if any colony doesn't like the tariffs put on them they can use their own starships to wrestle control of part or all of the zone that they inhabit.