Besty, I love Nia too, don't get me wrong (Toni Collette and Nia Vardalos singing showtunes in CONNIE AND CARLA was a dream come true) but I cannot picture her as the critic turned producer who basically wants to ruin Guido's career. I don't see her being as much of a threat when she sings "The trouble with Contini..." section of "Folies Bergeres" (assuming the number is still there and that Necrophorus' section is still in). I can see why you'd suggest her though because Stephanie Necrophorus is a character that's so pretentious and obnoxious that you just have to laugh at her which Vardalos would play to a T. Still can't see it though.
Marissa Tomei should play Carla, she's beyond ideal for that part. One of the few actress I think could beautifully nail both of Carla's numbers.
I would really love to see at least a stage star like LuPone or Donna Murphy or Jane Krakowski (would've been the happiest if she had been asked to reprise her Tony-winning turn as Carla) somewhere in this movie.
It'd be great if Marshall did another nod to the original production like he did in both ANNIE and CHICAGO. Perhaps we'll get Liliane Montevecchi somewhere in the film? (I believe she's the only one of the cast who has some kind of film career and is...well...alive).
"Some people can thrive and bloom living life in a living room, that's perfect for some people of one hundred and five. But I at least gotta try, when I think of all the sights that I gotta see, all the places I gotta play, all the things that I gotta be at"