Heat (Action Edition) - This would basically remove as much of the family drama stuff, and the kid trying to kill herself stuff, and some of the other character's relationship drama stuff, and keep only what's neccessary to keep it a lean mean action movie. Might not work, but it would be interesting,
We Were Soldiers (Green Edition) - Basically this would be an edit that included only the moments in the movie when the soldiers are in uniform and fighting, as well as some of the training stuff from before they get to Vietnam - and the French getting killed. As much, if not ALL of the "homefront" wives, and kids, and death notices would be removed.
The above two would sort of be along the same lines as the Pearl Harbor (which was on my wish list, but no more thanks to...) ADM edit, but neither of those two movies are bad. It would only be for personal enjoyment, and not to correct a bad, or missed-opportunity, movie.
One other edit I have always wondered if it would work is Transformers: The Movie. I would love to remove the cheesy hair metal band soundtrack, and replace it with some cool battle orchestral music. I don't know if that's possible, but it would be neat.
Oh yeah, I always thought there was a potential "De-Assified" type of movie in Catwoman. I'll probably go to hell for thinking that, but I think there is a possibility.
I have more that I can't think of right now. Oh wait, a good solid edit of the Godzilla movie could make that better. Somehow remove as much of that blond girl as possible.
Oh yeah, and Hulk could use a good re-working. Somehow take all the flash back stuff, add it to the beginning of the movie, and then tighten up the rest a bit. I liked the movie, but a good fan-edit of it would probably work. Also, someone that did this would have to add the sound of the Hulk changing from the TV show to when he changes in the movie. Also, the ending-credits theme song would have to be added to the end of the movie at the start of the end credits. When it's over the normal music could pick up.
I'm thinking of a few more. Is this what you were looking for?