Interestingly, I was following some Sondheim boards around the time of casting for Sweeney Todd, and a lot of folks wanted to see Anne Hathaway as Johanna (she is apparently a very good singer, and I think she has performed some pieces from Sweeney Todd). Interestingly too, she would have had to have become blonde for the role
I don't know if she was even on Tim's radar at the time, but now that she is, who knows? I could see her as Vicki.
As for Helena, the lucky thing about Tim always casting her lately is that he doesn't necessarily always cast her in a lead role. So really, if she's in Dark Shadows, she could be cast as anyone (Mrs. Johnson?? LOL) But Julia Hoffman seems to me like it might be a good fit for her. I don't particularly envision her as Angelique (i am still liking the idea of Charlize Theron), but I'm happy to keep an open mind for now.
The good thing is that DS is continuing to be mentioned in these articles!
Cathy