"Up" themed cable-car ride over a new South America section of Animal Kingdom. Rather than rehash the movie, the story should be that Carl is taking Russell back to Paradise Falls to get his "exotic animal watching" badge, and the speakers in your house-themed car would have dialogue between Russell and Carl explaining what the various Amazonian wildlife was. Then you could deal with another poacher looking for Kevin and follow her back to the labyrinth before returning home. Maybe a little too similar to Kilimanjaro Safaris' story, but using cable cars would be a very neat modification.
EDIT: Actually, even better, rather than Russell going for his badge in exotic animal watching, the guests would be new members of Russell's troop, and they're taking you along to get your first Wilderness Explorer badge! Dug would be on the ground, also broadcasting comments up to the house. CMs operating the line would be dressed as Wilderness Explorer leaders, and guests would get an animal watching booklet to fill out and keep, and could then get their badge at the post-ride gift shop. More interactive, kids love it, Disney makes more money off merchandise, everyone wins!