Daniel Bachhuber, a core contributor for a number of years, has just this Call to Action on the WordPress Core blog:
As you may know, Gutenberg uses the WordPress REST API as a bridge between the land of JavaScript and land of PHP. There were a whole host of conceptual challenges in translating WordPress internals to REST — and even more we still haven’t solved!
The post also linked to the GitHub Milestone for ‘REST API’ in the Gutenberg editor where a number of development tasks are open for discussion and assignment.
