Trying to piece together the relative locations of everything in space. We've got three galaxies, but a lot of what we're interacting with seems to be happening in Andromeda.
The original coalition was six planets, one of which was Sigius, which is in Andromeda. We know Urt is in Andromeda. Greedon and Septsu provided stellar cartography for the Vargen, so they're probably also in Andromeda. The Iron Quadrant is in Andromeda, and Vapus-10 going black hole cut off all the major trade routes into that quadrant, so Vapus-10 probably needs to be in Andromeda too... ah, confirmation Andromeda is where the original Coalition was in Sheep, okay. So all the original Coalition is in Andromeda.
We know that Krok the Propagator was operating in Andromeda, because Jezinka says the planet of Wren in the Bracken system is in Andromeda, which means that M-Lynn, Lahari, and Nyx are probably all also in Andromeda.
Ted Home World is in the Bethany Elliot system, which is based on those name-a-star kits, which means that Ted is probably in the Milky Way. But Minsky claims Låfftrax controls the Milky Way and is moving into Andromeda and Triangulum, which... may not ENTIRELY be contrary to how the Ted Empire operates. And the way Leif talks about the Teds in Leifs as the hall monitors of the Milky Way makes me fairly certain they're in the Milky Way. I suspect they were technologically advanced a lot sooner than most of the Coalition Planets, because they would have needed to travel to Andromeda at sub-light in order to show up with their warp gate proposal when they did.
What do we know about Triangulum... Verge calls it the place where all the deeply strange people are, it's where all the alien fungal strains in Cameron's house come from, Sigius has colony candidate planets there, Quilandis is not in Triangulum, outer rim of Triangulum is where the Teds were doing their time crystal experiment, and that's where Meesock's workshop was discovered.
I'm going to guess that Quilandis is in Andromeda, if it's not in Triangulum, because it's where Leif went to ground after leaving Låfftrax, which means he'd have probably wanted to get away from them.
Red's Rectangle is (I think) in the Red Rectangle Nebula, which means it's in the Milky Way. I'm going to guess based on that that the Galaxy Brain is also in the Milky Way.
Doesn't help that it's not really clear how long transit via Warp Gate takes, or how fast ships move in local space between stars. We know sub-light, we can maybe approximate something for moving in gravity wells based on the amount of time it takes for Verge to get from Earth to the moon, but that's not going to be the same as interstellar distances, because it sounds like the warp gate has to be actively attached to a star to work, so it's not like the Teds can have a warp gate closer to Earth than the nearest non-Sun star, and Leif managed a trip home to Earth in 8 days.