personally I'd favor this:
You only get points for a sortie if you rtb or ditch in friendly territory. If you die or are captured, you lose your points for that sortie.
Why? Because that was the name of the game in WWII - Erich Hartmann would never have gotten 300+ kills if he haden't: flown cautiously, used his brains, relied on wingmen (tactics) and avoided fights without the intial advantage.
Instead of recieving points yourself for sorties where you die/are captured, these points should go towards your country and be split up amoungst the players alive at that point. After all you helped your country by taking out a hangar, shooting down an enemy plane etc, so that effort (points) should not be entirely lost.
I know this is not going to happen but it would force ppl to fly smarter/use tactics "real WWII" pilots used whilst your average "enter the furball air quake dudes" would literally "die out"

Effdub