You have missed the best place so far. You have to go to Comal river in New Braunfels,TX. For TUBING. Yes, tube like in tire. You can rent one for $15, than you get to flow in a river with your beer. What can be better place than this?  Place is always full with people (in summer), crazy people. You will love it. 

For me it was a great experience. 

Cheers.