I have flown AA coach class multiple times between Dallas and NYC and maybe this feedback is biased due to the class I have flown and the fact that I am used to Indian "actually warm" hospitality. Nevertheless, I am told AA is the better egg in the basket of american airline companies. I will only write about the bad things. If you need to know about the good things, there’s their website!
1) They refuelled with us on board! I was taken aback because Americans typically are aware of and abide by "rules". If the rules fail to comprehend how dangerous it can turn out to be to refuel with people on board, then I have very little to say
2) The flight-attendants don’t care whether you are coming or going or if you found your seat. They are busy catching up on idle banter. Row-wise boarding is a good thing if you are row 29, you will have the right to occupy two and a half racks with your own luggage if you care. If you are row 5, then God help you and your hand-baggage, because the attendants certainly won’t
3) They serve you pretzels and soft-beverage of "their" choice - 66% of the times I requested them for sprite, they gave me Coke. The other 33% I asked for and got water without ice
4) Legspace is something that you should not expect. If you get a window seat, squeeze into your seat and jump to reach the aisle once you are home
5) The captain actually asked people to generally settle down and quicken the boarding process as "the sooner you sit down, the sooner we’ll all reach"(Excuse me, I did not realize I was traveling on a Delhi-Jammu night-bus!)
In the end, I must say, in most probability they will take you where you need to go, so just buy a cheap ticket and don’t wish for much more than the speed of travel.