Server Browser solution if persistent servers are an obstacle to having one.

Two solutions:

- In a server browser make a "dummy server" with 0 players show up when all the currently running servers are full, if enough people will join that "dummy server" game will spin up new server
 
or 

- Create a server browser system where if there is enough players in the queue to the server game will spin up new server with same parameters and will move people from the queue there 

P.S. Or a system that has combination of both.

P.S. This way communities or group of friends with more than 4 players who would want to play on the same server together would be able to do it without party system.