I have a suggestion:
Place your wormhole pilot device, thing, into your colony’s…. Waystation? Starport? Like a domain colony item. Anyway, while installed, if allows any fleet to use your wormhole if one anchor is inside the system with the installed wormhole navigation device, including your own.
Gameplay wise, this makes it so that every market in your system is considered to located at the wormhole with the best accessibility to other markets. So for example you could have a wormhole 20 ly from the core, but you put one wormhole in your system and the other in Penelope’s Star. Your colonies in that system now act like they’re at Penelope’s star for accessibility bonuses.