Wouldn't it be easier to say that, for all those flying less than 20k per year, the best bet is A3? Luggage allowance (seriously, who really takes THAT much luggage when flying? ), priority check-in, boarding and lounge access are good enough for, let's say "<20k flyers".

When it comes to redeeming, of course, it's another question. But if your fav airlines are in *A and you don't fly that much a year, then A3 is a good bet (for the moment).

A bit simplistic approach I know...