I love Maria Friedman as a director. I prefer her work as a director over her work as a musical theater actress (I saw her in "The Witches of Eastwick" many years ago).
I have to say that I don't understand comments like those from WorldWithoutYou or Macbeth. IMO, they give an impression that Cumming isn't the creative actor that he is, with the ability to find something new/interesting in a role previously immortalized by another actor. E.g., his interpretation of the Emcee in Cabaret superseded Joel Grey's as the model for being a "definitive" interpretation (at least, until another actor supersedes his).
I'd really like to see his Higgins. IMO, he's got a head start by looking very distinguished in his very early 60s.