maybe federated region-based backend to reduce collateral damage?

In fact it would be really nice if server can decide who joins from queue using some modding mechanic in runtime not using fixed CLI switch (API callback to server to decide who joins?). Would be useful to implement smart priority queues algorithms. Something similar could or couldn't be achieved by kicking irrelevant players and depends on qeueing use-case, but it will cause players to spam queue with connection attempts unlike when you have fully controlled priority queue they will just stay in queue idle.