If you're competent enough, you should be heading towards a founding engineer kind of job. "Refactoring, rewriting, sprint, agile, rearchitecting things etc aren't that fun" - exactly this, but at the same time, it generates insane amounts of experience, so your situation sounds like you learned everything you want about the bad processes and you're ready to implement your own good processes.

The things we don't enjoy most of the time carry stress and fear factors within, fear can be eliminated with knowledge, stress can be toned down with simplicity, if you already know all this you can turn any process into joy if you are having such responsibilities, or you can make your own from scratch