AA or UA or SW
I work for SWA. You really can’t go wrong with any of your choices.
SWA - unparalleled flexibility and amazing QOL and/or income potential living in a mega base.
AA - holy seniority movement...financials not as good as other carriers but your job is basically furlough proof due to retirements.
UA - decent seniority movement and the ability to switch between wide and narrow body flying. The most wide body flying of any major carrier and a huge base in ORD that goes fairly junior.
I envy your decision. Best of luck.