It should be noted quite emphatically that none of these techniques will work without people committed to the cause of writing quality software! Without a commitment to quality and ownership cost reduction, slipping into old habits becomes all too easy. If you have a culture where quality is held up as a virtue, but lacking real investment, the effort will not sustain itself.
Also, it's important to set the right expectations about the limits of these techniques. You can implement all of these tools and still have bugs. There's no universal salve against bug-free software, just as there's no "test" for whether a given software requirement or user story is desirable or correct. Like all things that have to do with people and motivation, the best defense against poor quality is a motivated IT workforce that genuinely wants to make things better. If you can combine that motivation with these good practices, you're likely to make more maintainable software.