Interesting post and a good read! I do a few MRs for AAdvantage status so this is of interest to me.

I hope you don't mind me making a few points and questions.

I'm puzzled as to your reference to the 'First section with the LAX Admirals Club'. I'm not aware of that and think you're referring to the Flagship Lounge - I'm a bit surprised that you had access to it on your itinerary. The same goes for you getting into the FL at MIA. The entry rules are pretty restrictive and I'm not clear how you qualified (was your companion BA Gold?).

I do agree on the poor condition of much of AA's domestic fleet. I think 'dirty' is often an appropriate description. That said, I think the F seats are generally better than you would find on a lot of equivalent BA short haul aircraft.

Finally, you did the right thing avoiding the 777 in favour of the smaller aircraft. I think I'm right in saying that a KUP fare on a 3 class 777 would put you in Business not First so many fewer TPs.