In known space there is a station that can be docked. This station stays in a specific place for one or two hours. Then it moves through system for an hour, ever so slowly, and can be seen on overview. These stations may offer services, have a market, may have limitations on what size ships can dock there, and there may even be a quota on how many ships it allows docking at any one time.
After the indicated time, the ship jumps to a random adjacent system. There’s a mean 10% chance this is a worm hole system. It then stays motionless for 2 hours, then moves around a bit and then jumps to another adjacent system, rinse repeat.
Mobile stations are likely to be owned by corporations such as Ore, or by an empire or pirate faction, and once attacked spawn defensive fleets. There are no Edencom or Triglavian mobile stations. They can not be destroyed. Docking may require a fairly positive standing. Those that recently killed another pilot can’t dock on any of these stations, unless of course
If this system is implemented there should be several of these stations, each with a unique appearance. They may have a preset “caroussel” pathway set out that takes them along a bunch of predetermined systems, but it would be far far more interesting if the tanker stations move around randomly, albeit some of these stations may opt to remain only in space friendly or neutral to them.
The arrival of a tanker station may have subtle effects on space weather.
There may also be a Jovian category of tanker station, and it is said about these that if you try find out what the owners look like you’ll lose shipping your privileges.