In response to Nancy's age: Shani Wallis was an incredible Nancy in the movie, my personal favorite, and she was in her early 30's when she did the role. Nancy doesn't have to be the actual 17 years old as written in the novel, we can look at any actress under 35 as far as I'm concerned.
I absolutely adore the movie (one of my all time favorites) but the show, not so much. Literally every five seconds there's a song that's usually not needed. I hate "I Shall Scream", "That's Your Funeral", "My Name" and the incredibly long "It's a Fine Life Reprise" and thought that the movie was smart for not including them. As far as I'm concerned, the show is slowed down because of those songs and "Oom Pah Pah", though a great number, was far less, well, random in the movie than it was on stage.
I guess this means I would rather the revival be more faithful to the film than to the original show. But I have no problem with that belief. As I've stated, the movie's better than the show anyway.
"Sing the words, Patti!!!!" Stephen Sondheim to Patti LuPone.