Monthly Automated GvG tournament in Obsidian Sanctum?

Would revamping Obsidian Sanctum into an area for monthly Automated GvG Tournament similar to the Automated PvP tournaments be good to have?

I could imagine them sealing off the domed arena in the OS just for this. The spectators seat will still be open to all players to stand and view the fights. The ringed area will be sealed off but transparent though, and only allow participating guilds to enter.

If this is a nice idea, what are the rules would you suggest to have? What are the numbers to allow for each match? The winners could have similar rewards to the PvP automated tournament rewards =3