I haven't tried it yet, but have a couple ideas - to expand on NatCigs last points...
Would it be possible to have the option to air spawn, and select both the distance from the opponent and the altitude of the fight? Obviously there would have to be some sort of agreement algorithm or some way for players to quickly negotiate these decisions, but I think it would add to this already great idea for an arena. My reason is this - in the DA, launching from the opposing bases as they stand now, a majority of the time of each fight is spent just in transit (not all the time, I realize some fights between = skill players last longer, but a great many don't), during which time players climb to pre agreed alt if it is different than the base alt, as well as gain speed. Even after that, most of the time is spent just nose on and waiting to close the distance.
If airspawning at say d6.0 at x altitude and y/z speeds were possible, the time spent actually FIGHTING/Training/etc, not just flying straight and level at the opponent waiting to close, would be drastically increased. This -as an option - would make training and duels a far, far more efficient proposition. In a 20 minute session I bet you could get in 2x as many fights or even more, compared to the way it works in the DA now, and if you still wanted to do it the "old" way from takeoff, have that as an option as well.
I can't wait to try this arena out, especially if it gets populated with a bunch of players, I think it has great potential as both a training tool to improve skills of all levels of players, as well as create "a league of its own" so to speak.