Great work on this project, a fantastic idea :)
I'd like to integrate some of the skill trees into the training/induction system at the Artifactory but would need to work with machine readable versions of the trees. It looks like progress has already been made on this front for the 3D modelling/printing trees and I wanted to check in before writing similar versions for other trees.
My main concern is the associated tech debt, ie keeping the JSON version up to date when the PDF changes.