Maniac if the goal is to just split up arena numbers. Naming isn't an issure.
Call them
Main arena 1
Main arena 2,
Main arena 3
All 3 with duplicate setups. This still causes many issues of flying with squads. And milk running empty arenas.
If I ever do split up mains, it would be forced what arena you fly in, i.e. by squads , then by some other meens for none squad members, would be mixed up on some time bases "once a day, or once a week", so you are not always flying against the same people, and would be entered into by just selecting the main arena, and you would be drop into the "Sub arena".
The one down side to this method is during realy low times, havn't come up with a solution im totaly happy with yet on this. But the force might be off once numbers drop blow some level.
HiTech