I think Markos is right that the choice is roughly between the "status quo" and the "new." Someone like Vilsack will carry on things as they've been, while people like Dean or Rosenberg would signal a new direction (though Stirling spells out clearly all of the reasons Rosenberg would be a bad idea.) Full disclosure, I've met Simon a few times.
I've joked that I'll support (not that my support matters of course) the person who promises to fire the most people. That isn't because everyone who works there is necessarily individually incompetent, but it's obviously a place where institutional stasis has set in. I imagine phrases like "we do it that way because that's the way we've been doing it" are regularly spoken.
The Dean/Rosenberg tagteam is an intriguing possibility. But, it's important to understand that the job itself is largely undefined. The right question is not " who is the right person to do X?" The right question is, "who has the best ideas for determining what X actually is?"
