Steve, you nailed it on the position of the tourbillon. I spent a day with Vincent Calabrese talking about his creation of the Blancpain tourbillon (and for that matter his work on the Blancpain Carrousel). The convention had been to place tourbillons at 6 o'clock. He did not want to do that because, as you rightly pointed out, when a winding rotor was added, it would naturally come to rest at 6 as well, cluttering the view in the dial port hole. So he put the tourbillon at 12, as he was already planning an automatic version.
Speaking of the winding rotor, I would guess by now you noticed Blancpain's little finishing detail on the rotor. of course it is hand carved on the side you see when looking through the case back. I would guess all winding rotors are finished on that always visible side. But Blancpain finishes the OTHER side of the rotor--since that side becomes visible from the dial port hole every time the rotor passes behind the tourbillon. I did not notice that when I firset got my tourbillon, then one say as the rotor wizzed by i saw the carving and could not believe it was there. Neat touch.
As for who was first to have an automatic tourbillon, Blancpain vs. AP I will research that. I know of the first AP torubillon, it was that strange looking TV screen on edge piece. What most people don't know was that it was ETA that did the watch for AP. Anyway i will check the facts on that.
Jeff