Perceptive analysis, Doc.
If one were to set out to create a character for the most powerful wizard, the one portrayed does seem a little undermanned.
However, I was just thinking that in all likelihood, Dumbledore fell into his job through happenstance, like most of us. Perhaps he isn't a perfect fit for it.
I guess like most of us, J. K. has no difficulty describing the actions and motivations of those who are evil, but real personalities have a quixotic quirkiness to them that makes them more challenging to capture.
We made it to the library and back without being rained on. Now I'm ready for the wind to shift and the temperature to drop 30 degrees.