If you're considering OCaml, you can also take a look at F# and Scala, both of which are languages that are influenced by the ML family but run on more popular

If you're considering OCaml, you can also take a look at F# and Scala, both of which are languages that are influenced by the ML family but run on more popular host runtimes (the CLR and JVM respectively) that gives them access to a bigger ecosystem.