Speaking as a "regular user" who just ran into this, my main concern is that PathLike paths get used properly. For filenames being passed back out, if I really want them to be Path objects, I'll wrap them in Path() anyway.

Please don't let a full conversion to pathlib hold up fixing passing a PathLike into the constructor. That's the main use case, and given how nicely most of the rest of the stdlib handles Path objects now, it's an annoying wart.