I just to make sure the Dominion is the nemesis faction for my kind in general.  

NPC-wise you will get Tikallians outside the Silent Imperium's operations. They're a species so you can always assume there's Tikali NPCs who aren't grand mission oriented, especially with the whole thousand+ years since the whole genocide thing passing.  Quite a few continue the mission as per the ancient oath however.

I think my first post should deal with what exactly that oath was as a prologue along with introducing the PoV character in present day.