i'll offer a "different" option. We just got a bunch of torchys (tacos and queso), bought a bunch of beer/wine, and then rented a party boat on lady bird lake. We cruised around for 4 hours, watched the bats, and mingled with everyone. Afterwards, we had everyone who wanted to stay out, meet up at a bar on Rainey.
We had a lot of people in from out of state, but even those who lived in austin or other parts of texas kept commenting on how it was the best rehearsal dinner they'd ever been to. It obviously wasn't the food, but it was the experience.
Even with the boat rental, we spent way less than what most restaurants were quoting us for dinner.