I think odoc and documentation writing, including .mld pages should be integrated in the language section of ocaml.org (likely around ‘Module System’/‘Libraries with Dune’).
The fact that the website has almost no mention of the fully integrated documentation system provided by the OCaml language is a shame in my opinion.
The documentation is fine for me but I’m likely an outlier, having spent the last 20 years writing ocamldoc :–) I think that @panglesd recent cheatsheet significantly lowers the barrier to jump into ocamldoc writing. However the question, which resonates with my comment above, is how people are going to find it. Most people will likely not consult odoc’s documentation pages.
Regarding the tool itself we are, with the upcoming introduction of assets, about to reach perfection, but there is this.