To answer one question posed by the original poster, I did in fact see the Florida pre-Broadway tryout of the show with Hunter Foster and Alice Ripley. Alice's performance was basically an impersonation of Ellen Greene and she didn't really do as much to make the role her own. It was my first time seeing her live though, and I think she's a great performer.
I don't have a problem with Audrey II being voiced by a female such as Jennifer Holliday. I think that would work very well actually. It can't be any worse than Billy Porter's performance.
The recent London production had a very different design for Audrey II which made her look like an overgrown weed. I can't remember any other changes right now
As to why the recent Broadway revival had a bad reception, my guess is that audiences generally felt the show was too overblown, big and brassy when it should have been on a smaller scale and in a smaller theatre. I didn't get the chance to see Kerry Butler, but that wasn't as bad as having to sit through Joey Fatone as Seymour. The best part about the production was Audrey II. Huge kudos to Michael-Leon Woolley and Martin Robinson et al for an amazing performance that still is one of my favorite Broadway memories. The three urchins were quite wonderful as well. Overall it was greatly improved from it's pre-Broadway tryout and I still prefer the Broadway version of the show to the movie, so it worked fine for me!
Dean: Can I tell you something?
Lorraine: That depends on what it is.
Dean: I think you're really really pretty.
Lorraine: (after a pause) Ok, you can tell me that.