Could you create a new main page forum in the Red Light District or Political Parties & Societies (HEM suggested Red Light but the latter might make more sense) called "States of Europeia" with the description "Sign up to join and participate in Europeia's state system."
Inside, could you create three subforums called "State A", "State B", and "State C" with no descriptions for now. Each should also have an additional subforum called "State A Private" etc with a joinable group for each state. They'll have real names and descriptions decided later by their members.
Could I have mod powers over all of this?
FYI, HEM and Writinglegend have been consulted about this setup. If there are any issues please let me know, but I think this is the best way to go. Sorry it's complicated.