As long as folks are friendly, both my main's plot, Vorkha Willowbrush, and my primary alt's plot, Yahneissi Darkleaf, are open to all. I have placed Exile and Dominion streamers at the entrances of both plots and made sure their colors can be seen for potential visitors. For RP purposes: Willow (Vorkha) is very uneasy around Chua (because she's Aurin and they kinda messed up her planet ) and Mechari (cool gemstones but weeeeeeird feeling in the Weave) but if they are friendly she will interact favorably with them. She has no issues with Cassians or Draken. Yahn (Yahneissi) has had to work with some pretty rough customers so she welcomes any and all to her plot but step out of line and you'll get a pistol shot to the face and none of that George Lucas crap either. She will shoot first no matter what faction you are
I like the idea of one of the posts here about putting a sword between the streamers to show that, while the plot is open to both factions, it won't be on friendly terms. This is on Kin's plot, which is in Cursewood, Celestion.