Agreed about the Sonny and Luca points, they should have certainly figured in the flashbacks. My god, the things Luca is alleged to have done in the book would have burned the screen. Sonny tells the Don in the book at that he witnessed the murder of Fanucci...could have been interesting.

But the return to Sicily was vital, especially to develop the friendship with Tommasino..and damn right we wanna see Vito tear Ciccio's guts out.