No need to apologize, Figaro! I actually didn't know what I was talking about, and I'll freely admit it--I thought the role's range was more complicated than it actually is, given the vocal pedigree of the ladies who've taken it on. But it's obvious that any role written for Gertrude Lawrence doesn't need a brassy/belty/soprano-y singer necessarily.
That said, I'd love it if Christiane Noll played Anna.
"You travel alone because other people are only there to remind you how much that hook hurts that we all bit down on. Wait for that one day we can bite free and get back out there in space where we belong, sail back over water, over skies, into space, the hook finally out of our mouths and we wander back out there in space spawning to other planets never to return hurrah to earth and we'll look back and can't even see these lives here anymore. Only the taste of blood to remind us we ever existed. The earth is small. We're gone. We're dead. We're safe."
-John Guare, Landscape of the Body