T8 flagship does offer a hot and cold buffet so you can still have a good meal you just have to serve yourself - much like BA pre flight supper in the club lounge! But I think the AA choices are better
both lounges can get very busy. People flying AA domestic are still people not monsters but given the flagship entry rules there aren’t that many domestic flyers in there.
T8 security - if your embarrassed about being taken to the head of the queue then just join the end of it and your embarrassment will vanish. You are not forced to use the flagship checkin.
T7 if the line at the priority security is too long then just go to main security. I’ve done that myself a couple of times and it was much quicker.
Oh and you can’t really avoid noise or children. At Christmas there is a higher chance of them being in the cabin.