What would be the benefit of rebuilding these components in Lit over using Vue to build them?
https://vuejs.org/guide/extras/web-components#building-custo...
* Built-in state management especially as in v3 (ref/reactive) is super powerful, and you can test the setup function logic by itself without any dependency on DOM which is convenient. By comparison, reactivity in Lit is basic (by design), and mostly work on the widget level -- if something changes, you need to trigger the update process of the widget.
* The lifecycle is also a bit simpler. In Lit, you often need to work with lifecycle callbacks like firstUpdated, connected, shouldUpdate, updated, disconnected etc. (You don't need to implement these for simpler widgets, but often you have to.) You can easily run into bugs if you are not careful, especially in the less common situation where your widget can be both temporarily and permanently removed from the DOM, in which case you need to make sure the state of the widget is properly perserved, which isn't a thing you need to worry about in Vue. We got bitten by this multiple times.
Unless there is a strong technical reason, I suggest that you focus on shipping features instead of changing your tech stack. Rebuilding your widgets is a very time consuming task with, well, near 0 impact on the user.