I found some graphs that I put together a couple of years ago. The results are born out empirically (at least by my experience in the OR). Lots of information about who to hire, who to fire, who to use under which circumstance, how to flip rooms, and more.
This is the type of graph that needs to be explained in an hour-long seminar. Personally, I think it’s a work of art, but then most parents think their children are cute. The graph is best looked at while drinking a cup of coffee and taking the time to see relationships.