AA has more retirements happening sooner. Someone hired today should be able to get into group 4 FO or group 2 captain in about 5 years. United has a better contract. Both are great companies to work for, so there's no wrong answer here. If you insist on commuting I would heavily favor the one with the easier commute. I would also consider which one has a base you may be willing to move to if you decide commuting isn't for you. I think United has hired more pilots and more younger pilots than AA has, so your overall seniority progression may be better at AA. AA allows you to reserve the jumpseat 8 days out. When I commuted, this was a huge deal.