One of the mistakes I make is in presuming that space is largely settled, mapped, and known. Some of the literature that I’ve been reviewing as I think about this game falls into swords and planet - explorers in strange lands that just happen to be planets they travel between. The whole things needs an air of the unknown.
Space is largely unexplored and uncharted. We don’t know most of what’s out there.
An ancient evil has been reborn. At one time, dark forces moved among the cosmos planting seeds and establishing footholds on a thousand worlds. Then, they disappeared. They have reawakened.
The ability to travel between worlds and between systems is a relatively new phenomenon. It is not stable and easy to use, but instead is unstable, unpredictable, and often dangerous to jump between systems.
More decadence, decay, and old stuff. Less new and shiny.
Think of worlds as city-states, or as collections of city states.
I’m thinking that one of the major sources of junker ships is a junkyard moon where hundreds of thousands of old craft were sent to die. I think of the Ming Dynasty who sunk their own Armada to cut China off from the rest of the world. I can see a culture that assumed a high level of technological progress, and then intentionally cut themselves off from the rest of the galaxy and shut it all down. They are gone now, but there are thousands of working ships sitting in junk yards that can be grabbed. The society itself is also gone - but there may be clues as to what happened to them.