You're right about Dr. Melfi—now that we're all pretty much convinced that Tony is unchangeable, what's the point? He's a terrible schmuck, irretrievable. We get it. I'm telling you, Tony's relentless needling of Janice really soured me on him; he's becoming his mother, which is interesting, but dangerous for the show, because who wants to spend an hour each Sunday night watching Tony behave like his mother?
OK, I do. So long as I also get to watch Janice give beatings to soccer moms.
You're also right about Johnny Sack; now that's a subplot. My wife, who is far more astute than I am, believes that Tony B. will be whacked next week, not by Johnny Sack, but by Tony S., or Tony S.'s surrogate, Christopher, in order to dilute the bad blood between the two families, but especially to get rid of a cousin who's nothing but trouble. I don't know where she gets these ideas, but she's generally right about things. For instance, she predicted that the finale of Friends would contain many moments of great emotion.
I'm also rooting for Johnny Sack, who is played so convincingly by Vince Curatola that he deserves his own spin-off show, like that guy Joey. (Have you figured out yet that I watched Friends last week for the first time in seven years?) Johnny Sack is a malevolent shit, but he loves his wife. And he is closest in demeanor and carriage to our idealized conception of a mob boss. He's loyal, ambitious, smart (no malapropisms placed in his mouth, unlike that of his nemesis, the buffoonish Carmine), and no one on television smokes with more style than Johnny Sack. Of course, nobody smokes on television anymore, but you get my point. The mob would be safe in Johnny Sack's hands.