As far functional languages go, Erlang, Elixir and Scala would get you further career-wise, and if you want to play in the sorta-functional world, Swift is also a high-in-demand language that borrows a lot from Rust and Haskell.

However, Haskell and OCaml are the more classic functional, static-typed languages, and while Haskell has more job opportunities than OCaml, it is probably the steepest learning curve and highest time commitment of all these languages.