Another issue with OCaml is that the community is small (although helpful). If you have very specific questions (esp. on more recent development), it may be hard to find help on Stack Overflow for instance.

Besides, the language has became quite complex: Monad-based concurrency and error handling, functors, objects, GADT, PPX... it's cool from a language point of view, but as a developer it can get overwhelming. You don't have to used all of this in your project, but still you may have to deal with existing code that is quite complex.