I'd come in and try for a rope, kill whoever I manage to draw up with me, then, since I'm a P38 pilot, half the furball would invariably go after me, because P38's are bandit magnets (fine by me, more kills

), so I'd drag one or two people safely away from the furball and trap them in a vertical stallfight.
As for who to target first... when I go hunting, I always find P51's particularly attractive, mainly because I always know I can beat them in a 38, they are nice and fragile, and they're annoying. The average Pony driver isn't a good pilot either, most likely a dweeb who flies it because he wants to be cool in the "Cadillac of the sky." The occasional skillful Pony pilot will provide a nice fight, but the 51 can't stand up to the 38 in the vertical, and most good Pony pilots will run once the advantage is lost.
All of the above also applies to LA-7's, who, like the 51, are dead in the water once speeds get low. I only find them dangerous if they're above me.