Wow, great insight all around. I think it speaks to why we all love these movies so much. You can discuss pretty much any aspect of the story.

One related aspect I had always wondered was that if Vito really placed the Tattaglias at the head of this deal with Sollozzo rather than Barzini, did it ultimately lead to his being shot. By this I mean it becomes known later that Barzini was behind Sonny's death, not Tattaglia, and Vito seems to think less of Tattaglia ("Tattaglia's a pimp, he could have never vouched for Santino"). If Vito knew that Barzini was the "driving force" behind this partnership with Sollozzo, would he have considered his decisions on the narcotics differently. Did Vito think Barzini was more dangerous than Tattaglia?