Dueling League

This is a One on One PVP arena style match. You face another player, Horde or Alliance doesn't matter, that's the same level as you, exactly. Except inside the instance of the dueling league, the player wears dueling clothes, automatically put on when a duel starts. The dueling gear is the same for one class, at each level. Cloth robes for Mages, Priests, and Warlocks, with no stats increases. No trinkets, no health pots, just player versus player, and gear doesn't matter. Rogues and druids would get leather, mail for shamans and hunters, plate for Paladins, Warriors, and Death Knights. Plate would give 4X the armor protection of cloth at the same level, but no more than the basic difference between cloth and plate armor. You'd get to choose a basic weapon for each class, which would be the same on each level, mages could choose a staff, dagger, wand, etc, but it would be the same. Hunters get choices of Crossbow, Bow, Gun, and get automatic bullets/arrows, but all do the same damage. Buffs from other players get removed, along with effects from potions, food, etc, upon entering a duel.
Certain class combinations are pretty unfair, like a Rogue vs. a Paladin.  No matter how well the Rogue starts, the Paladin could just bubble and heal, or use Lay On Hands.  Perhaps these could be disabled for these player combination duels, if it proves to be a problem.

Basically these duels would be about the skill of the player, not at all the gear of the player. Though some class combinations are unfair, so perhaps there could be trinkets or special health pots for dueling that a player could use to make one on ones fair between certain classes. This could be rated, and have elimination tournaments, so the best duelers end up facing each other. They could grant out of duel rewards so people want to do it more. Good off hand or trinkets for people of high rank, or high win percentage.