Like many people, I've been watching Dr. Who since Tom Baker, or maybe a little before. And I have to say that Ten is the first Doctor who doesn't seem quite alien _enough_ to me, while at the same time (as you say) he remains pretty oblivious to human behavior and emotions at times. Makes for decent fanfic, I suppose, but not for great continuity.

If you look at it as him on a learning curve, it makes sense. He's trying to mimic human behavior without truly understanding it.