Hey, Jason, I've done a sous vide brisket three times. I did it like you described...smoked for about 3 hours with rub, vac sealed, and in the bath for about 72 hours at 160 degrees. Then the normal char and sear to finish with extra rub to form a new bark. Two of them came out really tender, smokey, and flavorful. Couldn't hardly tell the difference between sous vide and regular smoking for 16 to 20 hours. The reason I said 2 out of 3 came out good was because the vacuum bag burst after about 20 hours in the hot tub on the 3rd one. I wound up with a 19 pound roast and 10 gallons of gravy. It was the only one I didn't double bag. The bag was just too tight for a 19 pound packer. Note to self: Always double bag large briskets.
You are correct on the Salt Lick method of cooking. They do cool them after finishing in the smoker and then reheat them over wood fire hot coals in their large round iconic fire pit at the entrance. They always taste really good. Several years ago, Jaxon, Albert, and I did a BBQ pilgrimage hitting 7 of the most famous BBQ joints in Central Texas in one day. They decided that they liked Salt Lick the best of the bunch.
Good luck with your brisket.