Great feedback, thank you for taking the time to test and share your insights with everyone.

The theme does not reliably handle the multitude of possibilities the site editor sets in the hands of end-users. This entire experience could be made smoother with a better theme.

It’s true that the theme could include more CSS to dictate aspects like spacing and smooth over visual inconsistencies.

I will say the approach for developing TT1 blocks is different than how a classic theme provides support for Gutenberg. Where a classic theme would express all of its style opinions via targeted CSS, contributors to TT1 Blocks are trying to express the theme’s style opinions solely via block templates and the global styles / theme.json mechanism. Anything that cannot be expressed this way, rather than writing a patch for it in the theme CSS, is viewed as an opportunity to improve the site editor and global styles.

This results in a theme that looks broken in places, and that's intentional for now to make the gaps obvious. That way the team can identify those gaps, and open issues + PRs to address them upstream in Gutenberg where the benefits will scale. Many of these issues are in progress or blocked: https://github.com/WordPress/theme-experiments/projects/1#column-12084948

The hope is doing it this way will lead to a better and more consistent experience in the long term. Would love your thoughts on this approach, and thanks again for your generosity in testing and sharing feedback :)