paint failing on plaster
Those walls look in bad shape. The fact that you've done so much work on them and they're still failing is not good sign. You can add drywall on top of the existing walls, tape, prime and paint. This would be a whole lot cheaper than removing and hauling away the plaster. I have not done this but I did go in afterwards to reinstall the electrical switches, outlets and fixtures and add box extenders. It seemed to be a great solution.