I'm not so sure that the "attaboy" landing message changed the way people play very much. Before that, the game would broadcast each individual kill number (something like "Kill #12 by Leviathn"). While that didn't encourage flying to live necessarily, it certainly didn't dissuade horde-like behavior or vulching. Of course, you could always tell who was vulching by the frequency of the kill announcement. Such a system in today's crowded arena would be completely unworkable, nor would many find it desirable.
Maybe a route more like ship guns is in order? If you die with more than two kills, it also announces your kill total to the arena. Something like "Leviathn died with 4 kills in a Spitfire Mk. V of +++ The Blue Knights +++" would work. That would still give "attaboys" to those who kill a lot, and while it would not necessarily stop hording or vulching, it could encourage some players to fly more aggressively.
-- Todd/Leviathn