Hi, I'm a newbie, and I have some ideas:
I recorded the video on a tape, so I remember quite clearly every part.
Here are the things that I wish would have been at least added to the film:
1. Grover and Gonzo - I saw them at least acknowledge each other: once when Oscar told the other muppets of the news alert on the television, I saw Grover and Gonzo standing next to each other, and looking as if they were chatting, and another time when the Fozzie and Ms. Bear talked to each other about who was going to sleep where and they looked up at Gonzo and Animal, who were sleeping on the wall, Grover saw this and I saw him acknowledge them.
2. Ernie and Lew Zealand - First off, I have no idea why Ernie did not have his rubber duck. Second, Ernie and Luke could have paired. Ernie could have told Luke that the reason he can not sleep at night, is because he wants to be with Luke, instead of Bert, and Bert could go hang out with some other muppet. Ernie and Luke have lots of similarities not to hang out with each other. But, they look nearly identical, sound a little similar, the both of them have a toy that they play with, the both of them are happy-go-lucky, goofy/zany, are surprising, the both of them love to play tricks on other muppets, etc. Luke could also have introduced himself to Bert. However; since Ernie and Bert are opposites, Luke and Bert may hardly get along.
3. The Muppets and the Fraggles - Kermit and Robin were the only muppets who were introduced to the Fraggles. Why weren't all the others? I especially think that the following could have met: Scooter and Red, Big Bird and Mokey, Beaureguard and Boomer, Webbly and Beaker, and Goober and Gonzo, they have similar face and body structures, or at least similar structures.
4. Oscar and Statler and Waldorf - Oscar could have introduced his girlfriend, Grungetta, to Statler, and Statler could have introduced his girlfriend, Astoria, to Oscar, if Grungetta and Astoria were both in it. Oscar could also befriend Statler and Waldorf.
5. Herry Monster could have interacted with another muppet. Since, he is friendly, inquisitive, and likes to exercise. I can see him talking to at least some other muppets, if not many. I kind of see him talking to Crazy Harry. But, I do not know which of the "Muppet Show" muppets are exactly friends, except for the main muppets.
6. Cookie Monster and Animal - I know there was a scene in which Cookie Monster took the cookies from Janice's tray, and Janice asked Animal who it was, and Animal said someone he could look up to. But, there could have been much more interaction between the two muppets.
7. I also wish that more of the muppets from "The Muppet Show" could have been in here. But, oh well.
Anyway, I am sure there are a whole list. But, this is as much as I can think of.
Muppetmonster