Short haul domestic/transborder Y - Porter, AC, DL, UA, WestJet, AA

International J - SQ, TK=AC (tie), LH, BA, UA, AA, EK, TG

Ranking is by pleasantness of the experience. Adding schedule/routing often changes it, as can plane type. And occasionally I succumb to mile-chasing (i.e. X will give me 250% miles while Y only 125% etc).

Some explanations:
BA gets penalized since I don't sleep well in their Club World seats, and sleep is the one comfort thing I actually care about (much more important than food or staff attitude)
EK gets penalized since though they feed you well and fawn over you (excessively!) when things go wrong they have trouble sorting it out, or maybe don't feel like it if you're not a frequent flyer with them.
TK vs AC is a toss-up. Love the food and service on TK, and the IST lounge, but ground staff are clueless and simple things become complicated. Food on AC is mediocre, but the pods (except coffins) are easy to sleep in, and I've never had an issue with staff attitude and know some of them personally by now.
SQ is great, but something about seeing the poor flight attendants smile fakely at you and squat down for the 300th time to be politely "at your level" makes me uncomfortable. (AC can get dangerously close to that level of smarminess when the SD, his/her mind on a dozen more important things, has to come by and "thank" me as a S100K 1MM for flying with them. To be clear: I don't mind the recognition when it's genuine, but it's eyerolling when it's forced and artificial)