I would like to retract my suggestion for language family-based menus. It would only work if everyone was a programming language nerd, and even then it would be annoying.
I think the best way would be to have it read completely from a `.conf` file (as it does now for custom filetypes) so that users could choose their own organization and/or hide languages they do not use, as suggested by @rubyFeedback (and previously discussed with @elextr offline). The default `.conf` file would of course use a sane organization (ex. alphabetical) for those who don't care to fiddle with it.