[Exuma]

"very limited uses" mmmmm what? Reactive frameworks are one of the widest used front-end design patterns.

You answered my questions with a bunch of theoretical non-answers that comes off like a tech purist who hasn't actually used the technologies but has a lot of opinions about them. Do you have a lot of experience designing non-trivial/complicated web apps with very heavy front-end features? "layout engine", "widget hierarchies" what _exactly_ does that mean in the context of designing something as complicated as Google Analytics/FB Biz Manager using javascript. If you are proposing not using primarily JS logic but rather server logic, or not as a SPA (or isometric hybrid like nuxt/next), then that makes me want to hear your answer even more.

Answer the question of: how would you do it?