None of that it's going to help much. You need a true sound barrier a true sound wall. Actually there are types of sheetrock that you can buy that are expensive but it's perfect I've used it in rentals but nothing will be better than a staggered stud wall with no contact but then you have still noise over the talk and under. I've insulated a lot of apartments in my life. The next best thing of course is the arrangement of the rooms kitchens should be back to kitchens and generally a living room to a living room bedrooms always on the fathests side of the house. The common party wall should ideally just contain the stairs and a hallway