> That pretty much works now?

Well, with the requisite glue code that would inform each user's Prometheus instance how to scrape the service instances -- yes, more or less.

> is not at all clear to me how doing a purer version of Prometheus would make any of our users happier.

If the only things you care about when you build systems are "works" and "direct impact on customers" then there's not really a point to this conversation. The things I'm speaking about, the architectural soundness of a distributed system, are largely orthogonal to those metrics, at least to the first derivative.