If you're planning to be out west anyway, I strongly recommend a visit to the
Caverns of Sonora.
Call ahead and make sure you can get ground transport; last time I was there, the airport had a loaner van and they were very liberal with how long you could use it (I don't think it got a lot of use!). But that was several years ago (2017?) and the van was pretty old already, so I dunno if it's still on the road, and for years before the van they had nothing, so...call and check. A few years before they got the van (2014ish?), there were no local rental car options and no taxi or Uber. I considered landing at San Angelo (nearest car rental option) and driving to Sonora once, but that's a longish round-trip considering there's not much else to see in the area. I ended up not going then, and only reconsidered when I learned about the loaner van some time later. (Not sure if the taxi situation has changed since then, so check that too...)
Despite the ground transport issues, Caverns of Sonora is an amazing place, and worth the effort. Carlsbad is bigger, Natural Bridge (and pretty much every other Texas cavern) is more convenient, but Sonora has features that you just don't see, and in quantities you don't see, in other caverns. (Even after the intentional destruction of its unique butterfly formation by stupid frat boys many years ago).
I've been to many caverns (just as a tourist, not a spelunker), and CoS is by far my favorite. It is worth making an effort to visit.