I agree with jdc in terms of your walls and just doing a skim coat. I prefer drywall to plaster, but…why do you hate your plaster so much? From what you describe it’s not apparent that it’s necessary to gut the house, unless you actually want to do the umpteen things jdc describes. If you hate your plaster because it’s not smooth, do a complete skim coat–if you do it with someone who’s good, it’ll end up looking like drywall. We did a skimcoat in our living room–the walls were awful (buckled, uneven, awful) and now they look like drywall. We were charged roughly $1,000 to do the skimcoat on the walls and ceiling of our large living room and paint it. We got an estimate of $800 for the same for our dining room (where the walls there are in better shape). Try that–it may save you a lot of money and avoid a lot of unnecessary work. But if you really want to gut, hey, your contractor will love you–just not your wallet.