Let's start kicking around constructive ideas, shall we?
"Q-Space" is an old idea I had for RPG-friendly FTL. I originally came up with it ages ago, when I was playing CHAMPIONS, and applied the Hero System conceit of different "Combat" and "Non-Combat" speeds to FTL Flight, the only movement power that didn't have it. When I realized the sociopolitical ramifications of Slow-Then-Fast FTL, I kept the idea on file, and actually used it in a GURPS SPACE game -- that game ran about twenty years back, so this idea's been kicking around for a long time.
The basic idea is that there are different regimes where The Rules Are Different:
- C-Space is the regime where the speed of light is "c": i.e., "normal spacetime".
- K-Space is "Slow FTL": about a light-year per month, for extended travel.
- Everything is conveniently scaled for swooping sci-fi FTL battles, and looks like Jack Kirby drew it.
- Masses (ships and planets) appear proportionally larger
- Distances appear smaller
- Q-Space is "Fast FTL": multiple light-years per DAYS, maybe.
K-Space is discovered first, and is Good Enough To Scout and Colonize. Ships are sent out with colonists in cold sleep and crews awake and active, since K-Space is full of Space Wedgies. With months or years of travel time between inhabited worlds, colonial cultures develop in relative isolation, and a "spacer culture" develops unto itself.
After a few centuries, reliable access to Q-Space is developed -- and suddenly, these isolated cultures are all in each other's backyards.
They do not all get along.
To complicate matters, access to Q-Space finally increases Humanity's sphere of influence enough that we finally brush up against Galactic Culture -- and as far as we can tell, the Galactics don't care about our internal affairs; they consider the species the significant level of organization.
I love this idea, honestly. It's a simple, straightforward way to get a lot of radically diverse human cultures interacting closely.