I recommend you to pick Elixir.
I can't describe it without writing a roman but here are some points which I do love about Elixir.
- Elixir uses immutable datastructures all the time.
- Elixir syntax is inspired by Ruby <3
- Elixir strickly follows pattern matching.
- Elixir is mostly written in macros.
- Elixir allows meta programming.
- Elixir has great tools like mix which create, compile and test your project.
- Elixirs code documentation can be used for unit tests through running mix.
- Elixir runs without performance penalties on ErlangVM.
- Elixir can interop with Erlang code and libraries.
- Elixir inherits all the great goods of ErlangVM. (Too much to list here)