There is already
- PureScript - https://www.purescript.org/ - though it is closer to Haskell
- ReasonML - https://reasonml.github.io/ - essentially ocaml with nicer syntax
Both are strongly typed with algebraic data types
I like reason and rescript and I'm looking at them for inspiration but I'm not a fan of their async support. Still, I'm planning to write a lot more code in them just to understand them better.