I was also at the final performance. I went in expecting it to be bad and ended up giving a standing ovation with tears in my eyes. The cast recording is always on my Ipod, though I do have to skip "People Carry On" if I am driving or in public, because the tears start flowing by the second verse.
This show was beautiful, and the actors were incredible, but there was no way it was going to survive on Broadway without a major star or a more inventive marketing campaign. I believe it would still be running if it had opened off Broadway but that having the lure of "the Broadway musical" after the title was strong (and will make the show more popular in the future).
David walked into the valley
With a stone clutched in his hand
He was only a boy
But he knew someone must take a stand
There will always be a valley
Always mountains one must scale
There will always be perilous waters
Which someone must sail
-Into the Fire
Scarlet Pimpernel