For whatever it's worth, which might not be anything at all, I saw the show again Thursday night, and very little appeared to be different, though there were some minor changes, but regardless, I still enjoyed the show just as much as I did the first time. Even knowing everything that was coming, remembering the jokes and the imagery, etc, I was still very delighted by the show, still found it very charming and still really loved the music and the sets. I thought maybe I'd find problems with it the second time around, but I really just enjoyed myself all the way around.
I will say though, that while I don't mind the parts about Amelie's childhood, I definitely also wouldn't hate if they shortened that part, but it didn't feel as long the second time around, even though I'm sure nothing changed.
Also, for those saying the opening song needs to be changed, I completely disagree, that opening song, I feel, is perfect, it sets up the whole idea of breadcrumbs that the show builds itself on, the idea that one event or action leads to another and the way random paths end up connecting.