I love the classic “industrial” world. Crowded cities, polluted atmosphere, mass production, and serious wealth disparity. It’s pretty much insta-dystopia. Subsector creation rules make them pretty rare, but I think they’re a great starting place for a sandbox campaign.
Xingyun is just about in the center of the subsector, nestled into a modest J1 main comprising at least 19 worlds. From here, an enterprising tramp freighter could reach the trade caverns on Izanami, the endless oceans of Yemoja, the perilous jungles of Bandua, the metal-rich asteroids of Lofoten, and many more intriguing destinations.
Of course, considering the population of Xingyun, you could probably run a whole campaign without ever leaving the atmosphere. The thought of that makes me a little sad, but you could. A planet with billions of people on it has more than enough greedy schemers to keep the characters busy. And for characters who don’t muster out without a ship of their own, this would be the best place to gain access.
It’s also most likely where the characters are originally from, which is a bit different from the approach to the LBBs. Characters in the great grandpappy edition from 1977 are assumed to be newcomers to the region. Here, you’ll have history. You’ll have connections, and baggage. Heck, you might even have a medical condition because of that crappy polluted air. What was your SOC stat again?