The problem I have is the score. You have big bold operatic numbers like No One Mourns and No Good Deed, then horrific pop tunes like Dancing Through Life. Then theres numbers like Defying Gravity and As Long As You're mine that try (and mostly fail) to fuse the two genres together. And as always with Schwartz, if you can't think of a lyric, make words up or repeat them till it's painful.
As for Winnie's book. It's pretty unimaginative. The 'jokes' only fly when the actors do them right, and there is too much exposition. Every thing is explained in pretty much in simple English.
And the finale. The only problem I have with it is it's overly dramatic musically, but the staging is bland.
Reading my comments, I have been very critical, but I do myself find the show quite entertaining, I've seen it twice and it's thrilling, but when I analyze and get to the knitty gritty, it is flawed.
A little known fact is that in the original screenplay, Pan's Labyrinth was Pan's FLAByrinth. Hmmmmmmm...glad they changed it.