[Poll] How should root zone mirroring be configured?

This issue is a spin-off of #33 (closed)/!329 (merged) that aims to facilitate discussion on whether named should mirror the root zone by default and if not, what the configuration syntax for enabling it should look like.

I will create a separate discussion below for each option that has been proposed so far. If you like one of them more than the others, please vote for it using the 👍 reaction. I imagine we will be able to come to a decision without resorting to negative votes, but if you feel strongly about one of the options, knock yourself out!

Unless it turns out to be unanimous, I do not expect this poll to be binding in any way, I would just like to know people's thoughts on the subject.

Options below will be presented in no specific order. Feel free to add your own idea by starting a new discussion.