really nitpicky but this symbol requires squinting to interpret. maybe you could use a count-based or area-based system instead? e.g. one pie slice for easy, full circle for hard.

this is a high-level point, but this whole section reminds me of boundary objects, like birdwatching reports, and how they're used to communicate information between scientific and non-scientific communities (e.g. Star and Griesemer 1989)

criterion

might be good to explain what the social science version of "coding" means (as opposed to regular comp sci "coding")