Ask HN: Cms recommendations for typical small-scale websites?

I'm not content with the cms options I know / have worked with (Drupal7+8, Wordpress, Jekyll, Grav,...) and am thinking about starting yet another open-source cms. But maybe I'm simply not aware of good options, so here's what I think a good cms should offer:

- Open-source license

- Widely used programming language

- Good/reasonable code quality (rules out wordpress)

- Reasonably lightweight (rules out drupal8)

- Custom content-types / page-types / entities without 3rd party libraries

- A backend with amazing UX usable for non-tech staff

- Customizable backend users + roles/permissions

- Well documented and thought-through extension architecture

- An api for form creation + handling

- Image handling: Configurable image styles/sizes and responsive images

- Multi-language support built-in

- Export + import of configuration/settings to files and store them in git

- Export + import of all content to files

- Server-side rendering if javascript-based

- Good performance with reasonable development effort

- Fast development cycles

- Flexible enough (with custom extensions) for 99% of small-scale websites

- Great security at every level (no dangerous file permissions needed,...)

To me this reads like a wishlist for a cms which gets out of everyone's way. But having worked profesionally for more than 10 years I have not come across anything that comes even close.

Am I missing some amazing cms's?

update: text formatting