Looking good George. I don't know the layout of your TT but had a couple thoughts for you. Depending where any cabinets or such may cross your repair area, the new FG build up may cause a problem with the wall fit. If so, they could be trimmed to fit but it would be a lot easier to only use one layer of mat behind those areas over your butter fill. No extra work that way
. One other thing to consider now that you have raw walls. A number of folks have glassed in wood blocking for a good attachment point for shelves, cabinets and such.