Also my idea would be something similar to blaze's but different.
What about clans?
/clan create "name" (Creates a clan, 1 user/player can only have 1 clan.)
/clan invite "name" (Invites a player into a clan, you can invite up to 5 people, why? Because of the map sizes. "Maps with 12 players, would be perfect for clan fights.)
/clan kick "name" (Kicks a player out of the clan)
/clan join "clan's name" (Accepts the request invitation. (Only the owner of the clan can invite.))
/clan disband (Deletes existing clan.)
/clan war "clan name" "map" (Invites other clan into a fair fight, and only the owner can request or accept the fights, also I think maps that haves more than 12 player slots, would be reduced.)
/clan war accept "clan name" (Accepts the invitation to a fight.)
Okay, so that's kind of it, I can't think of other commands >;P, Anyways, it would be kind of hard to code, but I don't really think so.. Or maybe.. Idk. But anyways, so let me explain a bit, to start a fight with other clan, you'll need all players to be online, if any player is not online, it would say "Couldn't request a war with "clan name", because not enough players are online." or "Couldn't accept a war with "clan name", because not enough players are online.". So, what's the purpose of this? I personally think that this would be quite fun to make another leader board, for the most clan wins monthly, or something. I don't know what
@rubik_cube_man would think about this, but that's just an idea.