Polish for sure is one thing I want to add.
But beyond the static documentation, the main next leap here is to have "real" experiments running inline with the documentation to put something tangible around the various themes and topics.
Imagine - at the most basic scenario - clicking a button and rapidly seeing an experiment execute. Behind the scenes it's a straightforward simulation with some treatment effect. That generates results and that's the first baby step in understanding.
From there, successive tweaks and changes are provided to demonstrate the various ways in which things can get better or worse.
Main point is to minimize/eliminate the ramp up cost of "running" the experiment to learn what it's really all about.