A straw poll in general would be great - Guido suggested it as a way to find out whether it was worth discussing councils at all if it turned out there was only one volunteer.
My evidence is the number of people participating in the governance discussion (excluding those who are only saying they can’t participate, who presumably wouldn’t continue being involved in the same system). Most of us have our areas and little desire to worry about things outside of that, which we’re seeing now, and a role like any of these requires a broader view. Surely those interested in taking the broad view would be doing it now?
Meanwhile, both of our proposals introduce a new area that no core developers have had to previously take an interest in: Evaluating and approving proposals (except Nick Coghlan, I guess). Eventually (hopefully!) I guess we’ll grow to C++ size and have people joining the core team with their existing skills in this area, but right now our mechanisms for joining the core team also require other contributions, which means multiple barely-overlapping skillsets.
For a specific example, most of my management chain at work are excellent decision makers. They know how to collect more data, when they have enough, where to go to find experts, how to think like customers, etc., but most have not written code in years. How do we get one of them into the core team so they can run for the steering council where they can contribute the most? Restricting ourselves to people willing to wade through PRs or mentorship programs excludes people who are ready to help out today, but are not and should not be “core developers” (and I used “core team” deliberately earlier, because that term makes a lot more sense under a model where contributors don’t also have to be devs or directly involved in dev-like work 
).