I just bought my last flight! In the end I decided that I wanted to leave from the Austin area instead of San Antonio, as that morning will be my only opportunity to visit the Hamilton Pools Nature Preserve near Austin. One way car rental is expensive, but not ridiculous, and I feel that it's worth the bit of extra expense to go while I'm so close.
Thanks to PIO giving me the heads up about SWA fares, I visited the website to check them out. I also opened up the AA website to compare times etc, and was thrilled to discover that they had a better sale than SWA!
So long story short, I have booked a flight from Killeen (about an hour north of Austin) to LAX via Dallas Fort Worth for USD 150. There were cheaper direct flights AUS-LAX, but they were all either too early or too late. The flight from Killeen leaves at about 4pm, so will give me plenty of time in the morning to explore the nature preserve and city of Austin.
It's a teeny tiny plane that only seats about 40 passengers, with a single seat on one side of the aisle and 2 seats on the other side. I'm kind of nervous and kind of excited to fly on such a small plane! I called AA to make sure I would still get my full luggage allowance before I booked.
I've only got an hour to transit at Dallas, finally arriving in LA at about 7pm. If I happen to miss that flight, there is another one getting into LA at about 8pm, so still in plenty of time for my next flight, which doesn't leave until 11:30pm.
I'm really loving my status privileges at the moment, feeling pretty smug when I can choose ANY seat I want at no extra charge (including Main Cabin Select and any seat reserved for elite status members). Plus I've applied for a free upgrade on the Dallas-LAX segment

It's looking less and less likely that we'll be able to re-qualify

so I'm trying to make the most of these opportunities while I have them!