Wow, kudos, you've really outdone yourself with this thorough analysis.

I'd like to add on the flashback, which I found in particular fascinating. Here we get a first glimpse of how vampires make love and of the images they can get from the blood. While the latter is merely hinted at here, it gets later so wonderfully explored in Francesca. I wonder what took them so long to pick up on this fascinating tidbit of vampiric ability. They waited almost to the end of the series!