If not for my very first question, I would have uploaded a "preview release" to CPAN already.
If the answer to that first question is (as I suspect) "No, put it at top-level", then I can start making early releases to CPAN. I expect that "0.0.0 alpha N" is a reasonable version number for "no code yet". :-)
And there seems to be a small misunderstanding: I am really asking for an API design review. There is effectively no code written yet because I am hoping for monks more experienced than myself to say either "Yes, that API is sound and will be a good addition to CPAN." or "You will have problems here, here, and here. Have you considered ...?" before I put too much effort into writing code that will make problems later.