What we really would need is a match making system where you register to a queue and you get to face a random person selected from that queue by elo and a toutch of randomness.
We could make it external but we would have to set it up in a way we can track games and games are properly hosted/played.
So maybe we would have to pair that system with a hosting bot that would host the games for players and give them time to get in the game and if they leave before it starts or do not join within the allocated time frame they loose elo to make sure we avoid dodging behaviors if you dodge you basically take the loose.
Also players would have to have a certain number of games played before they can queue up in that to make sure we do not have too much smurfing problems I would say 1000 games or something like that