This is an interesting thread to me as I live in Boston and asm considering expanding my flying beyond AA.

I have to say I've been very satisfied flying AA out of BOS over the past 10 years or so since I abandoned DL, largely due to their mean-spirited SGB campaign. I find the routes, prices and service meet my needs quite nicely. I fly a few transcons a year and also travel quite a bit internationally, mainly to Latin America (where AA dominates) but also to Asia (where AA definitely lags, unless you want to go to Japan).

I get upgraded often (using upgrade points) and when I don't, as an elite I get first dibs at exit rows and other premium seats. And it's worth stating, that even though AA doesn't have E+ (something I'd like to try out), their coach seat pitch is much better in general than most, especially toward the front of the plane.

So don't count out AA out of BOS!

P.S. One other consideration is the notoriously cranky ground staff at BOS. I've heard enough reports to believe there is a problem. But I have to say I've been very satisfied with the service I receive on the ground. This is all very subjective, of course, as I had an experience with a CO agent in BOS that made me vow never to fly them again (and I haven't). Though most people feel CO has excellent customer service.