Nano im not at my home PC so cant check at the moment but if you go into the Deathmatch Gamemode BP you will see code for when Players first connect to the server and handling what team they are on.By default I believe it is setup for least amount of players on a team. Somewhere in there would be the changes you need to make. Not sure how to achieve that but thats where you should start. Let me know what you figure out cause Im still trying to wrap my head around that part.