Just read Vegan's thread, and partially agree with him, but there's an aspect of ganking and people who doesn't want to PvP. MY idea would be to keep zones as they are, and allow players to challenge eachother to a duel wherever. This would eliminate the constant ganking in arena when 2 people ar duelling, and it would make the entire world a bit more exciting to watch. You can even stand up close and watch a duel without being afraid of whos behind your back.
Just my 2 cents.