Hi Great topic,
My recent studies covered a large part of Leaderships & Management. Below are some of the people we looked.
Anything I've read, or watched by John Meada, has always been on the money.
These guys are no necessary Design/UX related but their well worth a bit of time. Great insights
Great insights into developing emotional intelligence
Sign up to his blog, little gems of advice arrive every day.
Tony Hsieh (Zappos)
Amazing attitude to customer focus, and how to engage emloyees.
Legendary CEO of General Electric, look up some of the stories around this guy, amazing stuff.