Hey Justin! Thanks for your patience. I try to respond much faster to your lovely write ups but was split between too many things last week to give this the proper attention I wanted to give it. Your final result looks rad. I see we both appreciate mountains! Expect to see the screenshot featured in the recap.

The most immediate issue when creating a new author template is that it was devoid of default blocks. Where was the—at minimum—header and footer?

Great call out. There’s lots of work around connecting patterns to the current new template part creation experience: https://github.com/WordPress/gutenberg/pull/39147 Right now, the work is instead starting with first adding patterns to the new page creation process but, in time, will be part of the template creation process too. With that said, it does feel like a missed opportunity and subpar UX for 6.0 for these to be blank: https://github.com/WordPress/gutenberg/issues/40238 I’ve opened an issue as a result to at least track this even though various pieces of work are swirling around it.

I was surprised that the Avatar and Post Author Bio blocks worked. I tested these both inside of the Query Loop and outside of it. When an author has published posts, the two blocks appear as they should.

As you found, there are some decisions underway around these various blocks:
https://github.com/WordPress/gutenberg/issues/24952#issuecomment-1088681428 While they all work, I do think the current experience is likely to be confusing for end users to have so many options.

It was also odd to visually edit a feature that is conditionally displayed. There should be an indicator that its contents may or may not be shown on the front end. I am not aware of any precedent for such a block in core WordPress, but we should look at other projects and how they handle this.

Totally agree with each point of feedback. I’ve had it on my list the last few days to open an issue around how the current dynamic breaks the WYSIWYG feeling so I created a bit more comprehensive issue to capture it all here: https://github.com/WordPress/gutenberg/issues/40240 Thanks for your great thoughts across the board. It’s such a powerful and neat block that to have a bit more of an intuitive feel to it would go a long way to help it be used properly.