The one thing that I have to say with respect to the current staff is that they: (1) appear tired, (2) increasingly appear inept (in Washington perception is reality), and (3) lack fresh ideas.
A shakeup wouldn't hurt. To use a baseball analogy, even the New York Yankees benefit from management restructing from time to time.
I'm not saying that all new folks need to be brought in. Nicolle Devenish, for example, is already on board. She'd be a great replacement for McClellan.