A couple of thoughts. When you say the acid is back, do you mean your tummy feels the acid/burning or you feel reflux and that old burning up the throat, or worse? I know you've discussed the "dumb organ" situation above, but I was just curious.
I am still on my prevacid solutabs and will be for the foreseeable future, per the doc's orders. I mentioned to him that I have some tummy acid and I'm burping a LOT which he said is normal with a posterior wrap. He asked me to take a dose of pepto in the morning to coat the tummy/protect it and to CHEW a couple of gas-x during the day to help neutralize the stomach acid/gases. I just checked to make sure there is a chewable form as opposed to the tablet.
Lastly, as far as exercise goes, I know that anything that causes you to tense up the diaphragm is going to be off limits for a long time. Walking, biking, swimming are all lovely forms of cardio that don't require that "grunt/push" that would come with weight training and all the other exercises you mentioned. Tensing and doing the ole "poop grunt" as my weight trainer calls it could cause problems at the surgery site so so be very kind to your tummy.