Not sure if someone has thought of this before, but here goes.
Create a special mission page for the DA. This mission page would have the following options for a duel (grudge) match. The mission would only allow 2 pilots to enter the mission.
The Wager: A window would be added to the mission page to allow the players to enter the amount of perks they wish to wager on the fight. A drop down menu would allow the player to select what type of perks they wish to wager. Fighter, Bomber, Vehicle.
Duration of mission: A drop down menu with the following options to set the parameters of the fight. Single flight, best 2/3, best 3/5, best 5/8.
Aircraft: This would pretty much be the same as it is now, with the mission creator being able to select what aircraft will be allowed to fly. An ALL Aircraft check box would be added so that selecting it would allow all aircraft.
An auto .ef (end flight) system would need to be put into place so that when one pilot is killed and it is recorded the game would automatically tower the other pilot. This is to ensure that a pilot does not start the fight with an E advantage by already being airborne.
If a pilot in a mission is shot down by a player not in the mission the kill does not count against the pilot. Both pilots in the mission tower and start over.
A system like this would allow a player to challenge another and set the conditions of the fight. Perks to win/loose, type of aircraft, and duration of fight. The person being challenged will be able to look over the mission/challenge set up and either accept the challenge or decline it. Once the fight is over the perks from the looser would be transferred to the winners account.
I figure this will give people an opportunity to put up or shut up, when they start complaining on 200 about how they got cherry picked or HO'ed by a dweeb, when in reality they just got out flown, and beat