We've tried that SIK1, a couple of us were hosting it in rotation for a while with the same settings. For some reason people seem reluctant to come to a privately-hosted arena.
Or they don't even see it because they are not on the the "all tab".
That's my theory atleast.
I'm with you. I wish the arena would go back to simple basics, but keep the airspawns. Continue with the 1v1 quick duels, but fix it so you can do 2v2+ fights. Make the AI in a different area than the free fight area.
A place for duels, a place for free fight with airspwns, and a place with AI to fight. All on one map. That's all you need. Remove scoring all together.