Jan 26, 2016, 4:52 AM

@faraday said:

I've had some experience managing these types of themes, but I'm looking for other peoples' insights. What's worked well, what hasn't?

I can only go with anecdotal evidence, but I think @Sovereign has a point there. If you want to allow PCs to come in "that have always been there," creating a roster of the extant population by concept might work.