I fly 65k a year of work travel, with usually 60k of it being in the really cheap fare classes like L/N/Q. With EXP in range, I've started to fly 35k/year for fun, and it's all L/N/Q. I'm sure that AA wishes I'd fly more Y/B, but they'll take 35 business round trips a year, but they're the ones that set the pricing structure...

• ]Status makes travelling for work less stressful with perks like being at the top of the standby list, the dedicated ORD EXP check-in line, etc.;
• Miles let me take companions on international trips, which lets me take more trips; and
• Upgrades let me travel in comfort when coach is full or the flight is long.

If I didn't travel for work, I doubt I'd fly 35k/year for leisure. I'd probably just take one domestic and one international trip a year and be load-sensitive (fly when loads are lowest to get a seat next to me free in coach) more than mileage-sensitive.