As promised, here is my review of Kickapoo Cavern State Park, in case anyone is interested in going sometime.
The drive there was beautiful as it's deep in the Hill Country and although the last town (Rocksprings) we went through to get there is about 30 miles away, it took 45+ minutes to get to the park. The speed limit is 55, but we didn't spend much time going that fast due to the winding, but scenic, road. Brackettville is 10 miles closer to the park, but in the opposite direction. Give yourself about 5 hours travel time to include stops for gas/food/breaks.
The park used to be a working ranch and is relatively small (6368 acres) with only 15 camping spaces available. 5 have water/electric and 10 have shared water only. Sites are clean, but close together. The trees/brush (mostly) keeps people from seeing each other, but you can still hear conversations. Fortunately, everyone was respectful and it wasn't a real problem. There is also a centrally located mens/womens restroom with hot/cold running water and showers. Finally, there is a separate group camping area, but it's only 5 spaces in a 2 acre site.
There are actually 20 caverns in the park, but only one big enough that you can get a guided tour of. The bat cave is free and you can watch the bats leave every night from mid-March to the end of October. There are quite a few hiking trails and boots are highly recommended as most of it gets pretty rugged. Overall, it was a great time.