I spun up a mystery cult at the location for Sub Rosa #3.
The issue includes the map of the Great Sanctuary on Samothrace and a number of seeds involving the cult.
Sub Rosa #4 has a related covenant site for the cult, the ruined Thracian temple-city of Seuthopolis.
They might be worth checking out.
Sundered Eagle is definitely going to be a good place to look at for some ideas on mundane life.
-Ben.