I'd love to see a duel circle that allows you to use your PvE kit.
Duels with the new PVP system are just not fun, a friend of mine described it as "action figures banging into eachother until one of them breaks" pretty accurate IMO. This duel circle could take place in one of the new SB zones, so if you'd want to duel with the 4.0 PVP system you can go to Wolves' Den Pier. Maybe even add an option to do a 2v2 or 4v4 duel (or 1v2 even lol.)