Now, my idea would be that derelict ships and stations could be found randomly across planets/in space. the ones on planets would be just for salvage and have no functionality, but the ones that could be found orbiting suns would act like mini planets. you would orbit near them and beam into them, some would have oxygen, some wouldn't. They would be random in size/race of the ship and sometimes security could be found still protecting the long forgotten ship. You could repair the ships and take over these ships (if possible) and then use that as your ship forever.