I use pure no-build lit for the "interactive islands" the repo describes. Nice to see others have the same idea even if we're not taking the same approach.
You can consider Cami as the light dom sibling of Lit (which uses shadow dom).
Cami loses out on slots & style encapsulation, but you can style Cami components with normal / global css like it’s part of the normal dom. And since there’s no shadow dom overhead, it’s more performant and there is no FOUC if you load CSS in <head>.