Have you thought of purchasing discounted Southwest gift cards? You can do an online search for the best deals. Searching, I found this site:
https://www.giftcardspread.com/buy-s...s=72039-deddd5
Or, warehouse clubs, such as Sam's Club, sell discounted gift cards.
https://www.samsclub.com/sams/sw-air...17=1o4&veh=sem
You can use the gift cards to reduce the ticket cost anywhere from a minimum of about 3% to 7.5% or more, currently.