Currently Elixir is pretty much done and can't be made [much?] better. I work with it for 3.5 years and I can't see how it can be improved inside its current environment.
So trying to reach for strong static typing and zero-copy message passing are natural next steps -- and if that's not possible with Elixir itself, we'll search for it in other languages.
Making it faster for certain things, as long as that doesn't hurt it in other ways, is always going to be a win.