You should add an option to select ARENA(-S) that player is willing to play on. Implement this arena(-s) being pre-loaded into RAM. This, if player selects small amount of arenas, will lead to reduction of used RAM and players will only disconnect due to GPU or internet problems. Less annoying failed to load arena bs!
This will also help exploring new arenas faster. Matchmaking needs adjustment anyway, so please consider implementing this. Let us enjoy the game and become masters of our favorite maps!!!