I think that pitch selection is pretty interesting. I've written about it before, and will doubtlessly do so many more times until either all Rays fans discuss pitching in terms of Nash equilibriums or someone can convince me that another such delusional article would be essentially a hopeless waste of intellectual effort. (If you're not familiar with the concept, don't start by reading me. MGL has a much better explanation here on Fangraphs.)
I also really like pictures made from pitch f/x data. I've tried to give a comprehensive visual representation of how an individual pitcher works (here's one of Colby Lewis), but the problem with this method is that while it shows what the pitcher actually did, it does a poor job showing how well it worked.
Check out this prototype of a new graph model to supplement the strikezone plot. I used the recently acquired Fernando Rodney as my test subject. All input on how to make it better is appreciated.
My data comes from Joe Lefkowitz. Pitch type classifications are from MLBAM with my own edits. I've also simplified the pitch results. As for the pitch type linear weights, for balls, strikes, and fouls, I used Joe Sheehan's numbers on Baseball Analysts. For balls in play, I used the numbers given by Tango in this thread of The Book Blog. Note that those numbers are a departure from the pitch type linear weights listed on Fangraphs, as Fangraphs uses the run value of the outcome of batted balls, not just the average run value of the batted ball type. Also note that in these calculations, the balls, strikes, and fouls are adjusted for count; the balls in play are not. I would love input on if doing it this way makes sense.
As for reading the graph, in the "Pitch Type Linear Weights" tab, the height of the bar signifies the number of times Rodney threw a pitch in the selected situation, the color is the run value of the pitch per 100 pitches (you can see the exact value per 100 pitches by hovering your cursor over the bar), and the number above the bar is the total run value accumulated by the pitch type. A negative number means a better pitch.
In the "Results by Pitch Type" tab, the height of the bar still signifies the number of times the pitcher threw the type of pitch, but I've now broken it into pitch results. The numbers inside each pitch result type are the runs given up or prevented per 100, so you can see exactly how the pitcher is reaching that overall run value for the pitch.
Once again, this is a prototype, and I really would like input. If you don't understand something about the graph, ask. If you think I could show something more clearly, tell me how you'd rather see it. If you think my numbers are bogus and poorly conceived, do let me know. I think up to date run values are available in The Hardball Times Annual, but I've never actually read one before, and I didn't realize until recently just what an oversight that was.
Edit: Here's a mockup of Chris St. John's suggestion.
Edit 2: And here's another take on Chris St. John's suggestion. I prefer the latter. Thoughts?
Edit 3: One slight tweak, now positive run values will always be red, and negative always green.