I feel this is true of Tufte in general (and I own his books and have taken his seminar): he has made, and finds, excellent examples of good design but his heuristics (they are never as strong as "rules") are rarely actionable.
If you want actionable, I highly recommend Jean-Luc Doumont's "Trees Maps and Theorems." It's like a way more practical, actionable version of Tufte's work. Probably my favorite book on communicating with data. He's a great speaker as well, do take the opportunity to see one of his talks if you can (I believe some are on YouTube).
I completely agree! Doumont often gives talks at universities that are open to the public.