That is just it, in a nutshell. You will never know which strategy is successful, without hearing from the guys that are ranking. I agree with you, for the most part, but I can tell you from firsthand experience that flying to live WILL NOT rank you high in this game; not in and of itself that is. It seems the two most critical factors are kills/time-online and gunnery, but that is just the fighter/attack categories.
Okay, amend my statement to read: Proper strategy + success = rank. If your strategy is to live and kill with impunity, and you climb to 35k every sortie, YOU WILL NOT RANK unless you NEVER die. I suspect even then that the scoring system is stacked against you, but let's wait and hear what those in the upper ranks have to say.
My feeling is that if you were able to always launch straight into a low furball direclty over your own field, kill five guys quickly every sortie, and land most of them, that you would quickly outpace someone that never died at all.
But, you are ignoring two other categories completely. Buffs and vehicles/boats figure into this too. If you ignore them you can't rank, either. There are a lot of people that will never care about rank for that very reason.