Decided to switch here (and I owe you couple answers on GitHub, I remember that 
. But topics are quite huge, didn’t get enough time to explain my thoughts)
Thinking about your idea… it would require a fairly complex interop of LiveView / JavaScript, mostly when it comes to slots and nesting components. I’m not sure if it’s really possible, since vue components woul need to be rendered differently depending if it’s nested inside other component or not (to avoid creating multiple root-level components)
But maybe I shouldn’t write here since it’s not the topic for it
I think integrating client side hooks is a necessity for good UX. Recently there was a quite huge drama on twitter how LiveViews doesn’t scale because of delay between interaction and change in UI in Hey application. This could be avoided with hooks. Just it’s quite challenging to write complex components using hooks because it’s imperative - you have to control all changes by yourself, there is no way to declare a template and ask library to keep it in sync with the state… that’s why I’ve created LiveVue
The only really missing part currently is a shared state: by “shared” I mean shared with the backend LiveView (I believe it’s quite simple to have global state shared between all - even related to different roots - LiveVue components via a singleton module or multiple). I still think that pinia with a custom store plugin could be a good candidate for that. But custom solution would work as well: something which will intercept specific messages from the frontend hooks and inject values into the socket. It’s just a basic abstract idea, I don’t fully understand how to get changes back to the LiveVue.
But having that it would be possible to have actual “reactive” connection between LiveVue and LiveView parts. Of course, it won’t be instant because of the roundtrip, but it is much easier than per-vue component useLiveVue().pushEvent/2. I would even urge to discourage people to use this method on a day-to-day basis (it can create bad habits 
components should avoid inject-like interactions); though I think it is a necessity to have this option.
