There are some nice tools as well: merlin, utop, and friends.
As to the ecosystem, I beg to differ: the ocsigen suite of tools (lwt, server, js_of_ocaml), Core, Bucklescript, etc. They're all amazing, well documented, and open source.
I think both languages are quite nice honestly. F# has become a lot more attractive now that .NET is more readily available on more platforms. I hope it gains more steam too!