Out of all the concepts of the movie, I really think making Statler and Waldorf the Marley brothers was one of the great ones. Inventing a role not in the book, similar to Benjamina Gunn in MTI... the ONLY way to get Piggy in there. If only they could have fit Muppets as the other ghosts, I think the movie would have turned out just a bit better. I mean, I love the concept of Kermit, Robin, and Piggy being the Cratchet family... I even love Bunsen and Beaker as the charity guys. I do indeed like the idea of Fozziewig, but I feel they needed to do a lot more with that. Probably showed them working first, like the Magoo Christmas Carol did. Seems that it would have been great for a Muppet character to be Scrooge's nephew... though there really wasn't anyone they could have used. Scooter would have been perfect for the role, but the character was yet to be recast. It's just some of the lulls in the film where there aren't any Muppet characters other than some unimportant background muppets.For that matter, if they were going to try and be accurate to the book I could see Richard playing a Jacob Marley kind of character; he kind of specialized in bad boy roles, lol.
I still say Animal should have been the Ghost of Future Yet to come, ala Pete in Mickey's Christmas Carol, revealing himself just as Scrooge's nightmare was frightening him awake. Could have had Frank do some ghastly ghostly moans that sounded serious too. That would have been a fun gag.