Margo - I agree completely about the more universal appeal of Equus. And the recent experience of The Normal Heart probably gives an indication of what would happen with Bent (which I do, however, think is a great play.) And I guess you're right about M Butterfly - I just remember seeing Wong and Lithgow and being absolutely blown away. And I knew the 'secret' going in, so it was all about the story of love for me.
As to Sheppard, I have to admit that his viability as an actor isn't why I want to see him live
As you know, I'm an Ian McKellan freak, so I would of course prefer him to do it. Having played Nugget a few lifetimes ago, I'd be most interested in how this piece could be presented again.