I also saw it and did not love it. I thought his heavy and lazy focus on the theme of hollywood to dictate the set/settings didn't help tell the story or illuminate what the show is about, and i thought the 3 dancing young Mary/Charlie/Frank were incredibly distracting and out of place and annoying, and also their choreography was often desperately trying to tell its own (distracting) story which was rarely clear, until it came to its conceptual conclusion at the rooftop scene where it was finally worthwhile, but by then I'd seen it coming and it didn't have the impact it was clearly meant to. But even if it had, having them dance their way through the show (in what very much seemed like a directorial vision IMPOSED on the text and not at all something the show seems built to carry) was not worth the impact of the end.
For what it's worth, the rooftop scene played by the 3 young actors was probably my favorite of the production. Made me wish they'd been playing the characters all night.