It also leaves open the possibility of a "soft exit", under which the South could retain voting rights but be exempt from many federal laws.
If you're not affected by federal laws, you should not have federal voting rights. Britain doesn't have voting rights within the EU too after their "exit", regardless of it being "soft" or "hard". That's not how a soft exit works, especially if people from other regions didn't have a say on it.
I'm not exactly opposed to regions being able to be independent, but that wouldn't be good for the game given we have 150 registered people, and a lot of them don't actively participate. The numbers aren't simply there to have a right-wing dominated Atlasia game and a left wing dominated Atlasia game. It would also remove competition from the game, resulting in an Atlasia where the dominant left wing party always win an election, and an Atlasia where the dominant right wing party always win an election.