Indeed, depending on branding, technology, likely community participants (and to a degree, the corporate culture where most of those participants work!), and the actual shared goals of your community, there are a lot of different “best” governance models.
I’ve documented the Apache process at a high level here:
Essentially the ASF has a small core set of invariant rules (Apache License, Apache Foo project branding, +1/-1 voting and committer/PMC governance by merit, core infra services run by the ASF), a whole bunch of best practices, and a whole lot of wildly varying projects. So when you talk about “how Apache does X”, you’re really talking about how 150+ different top level projects (TLP) do it.
The essence to contrast with your Ubuntu description above is that the ASF has a Board elected by the Members that appoints corporate/executive VPs to set core policies and run branding, legal, infra, etc. operations for the Foundation (as a corporation) as a whole.
Then, we have 150 TLP Project Management Committees (PMCs) that each independently govern their own project’s direction and community management. From the ASF level, there is zero top-down technical direction: projects are completely free to manage technical affairs themselves, and the ASF is happy to even host competing technologies or projects. So the ASF board is a little like your Community Council, and each individual PMC is kind of like its own Technical board.
Separately, as a 501C3 public charity, the primary mission of the ASF is to produce software for the public good. From that core principle, we also mandate that individual Apache projects be governed independently of undue commercial influence: our goal is to give away software at no cost for everyone. So this is a really important essay to read to understand the Apache Way: