Just for fun, I went way back to the 1982 edition of the Birmbaum Guide. It had the following sit-down dining establishments in the Contempoarary:
Terrace Buffeteria, apparently one in a line of buffeterias now represented by Chef Mickeys.
Terrace Cafe, served an all-you-can-eat Italian buffet
Pueblo Room, also on the concourse, served "fairly straightforward meat, chicken, and seafood dishes" (I thought chicken and seafood were meat!)
Outer Rim, served dinner at the time. (no reservations)
Gulf Coast Room, continental cooking.
Top Of The World, buffets for breakfast and lunch as well as its dinner show.
I don't have any personal experience with any of these, as they were all mostly gone or highly renovated by the time of my return to the World in 89.
Also, at the Polynesian, there was the Coral Isle Cafe. But except for the name and decor changes, I'm not sure I'd say this was really different from the Kona Cafe currently in the space.
One last little note: the Dolphin opened with Ristorante Carnivale. I suppose the birdnfish people decided they didn't need two Italian restaurants, and so changed this to Juan and Only's.