That's a reasonable interpretation; I would happily make a merge request if there were a mechanism to do so. Roughly 2 hours of work between last night and this morning to accomplish a reasonable first pass.
The 5E ruleset is my primary interest, though I'm sure the concept would translate to others. I'm less interested in explicit integration points, though having one at the end would be useful, and more interested in more fine-grained definition of the functionality. There's a rather tight relationship between the Single Responsibility Principle and the Open and Closed Principle. In other words, if the code is broken down so that each function is responsible for doing one thing well, being able to extend any one thing becomes a very straight-forward process.
See
here.