One question I've always had - and I'll, right up front, state that NO, I don't have much twin stick time.
Is there a way to take advantage of differential throttling? It seems like, if the 109 can do a nose-point with rudder effectively enough to get a snap shot now and again, P-38 should be able to do so in spades with a boot of rudder and engine off, one side, the other on WEP.
I'll add, it is possible to have great fun with a 410. The penultimate time I sortied one, I shredded 4 bombers and was head for the deck to abscond with my ill-gotten gains. Then some clown called Fugitive showed up and shattered the dream. Last time I sortied one, some hyper enthusiastic clown in a pony collided with me. I landed some 12.7 hits on him but, generally, the rear armament isn't very useful.
And, of course, it's a very cool-looking brick, to be fair. You'll look good, even if you're going down more often than Alanis Morrisette in a theater.