Wow, someone had the opposite experience of CHAPLIN than I had... I thought the first act was rather promising and enjoyable and the second act where the wheels fell off and an utter disaster.
I agree (to an extent) about ONCE, in that the second act is the better half in terms of the story, but the first act is a more well-paced and entertaining one. I think that one is just so well-balanced and spread, that there aren't really weak stretches in that show at all.
Personally, I'd nominate INTO THE WOODS, where the second act's much deeper emotional core and moral ambiguity really elevate the show to another level for me. The first act may be more enjoyable on the surface, the second where the heart lies.
I think, though, there's a overarching point to be made about this; most musicals use Act I to win over the audience. A great opening number, a show-stopping comic setpiece or the establishing of signature songs from the score will all be best served by being in the first act. The second act is rarely more than tying up the story or paying off the seeds sown in the first act. The rare occasions of superior material in the second act can be cases where the show uses its two-act structure to tell a double-sided story (GARDENS and WOODS, as well as SUNDAY IN THE PARK if anyone thinks that Act II is better, would fit in here.)
Just my two cents.
Words don't deserve that kind of malarkey. They're innocent, neutral, precise, standing for this, describing that, meaning the other, so if you look after them you can build bridges across incomprehension and chaos. But when they get their corners knocked off, they're no good anymore…I don't think writers are sacred, but words are. They deserve respect. If you get the right ones in the right order, you can nudge the world a little.
