I decided to create a starter theme that included all the essential pieces, but left the opinion-dependent choices up to the the developer, and release it free on GitHub for other theme developers to use as well.
The Undefined Starter Theme for Ghost is what I came up with:
A demo can be found here. (Forewarning: an ultra-minimal boilerplate theme isn’t much to look at )
Let me know if you have any feedback or suggestions!