A book on communicating designs (this helped me a ton even though I only use it where necessary which isn't too often) http://www.amazon.com/Applying-UML-Patterns-Introduction-Obj...
Also this was transformative for how I approach leadership: http://sivers.org/ff
Also the Lean Start Up was big in spite of the hype just for articulating how thinking strategically about what you're building and for who can lead you to success.
Hopefully that paints a picture of how I think this list could be better balanced.