We've eaten at Coral Reef and we were pleased. The portions were not large, but OK...we didn't leave hungry, but I could have eaten more. The food itself was excellent and I think the atmosphere is cool with the aquarium. If your timing is good, you'll get to watch divers along with the fish and we thought that was neat. As far at the other Epcot restaurants, I think the best are Tempanyaki and LeCellier. Akershus is a little to funky for my family, Mexico is good, but I can get good Mexican at home. I feel the same about Italy. We have not eaten at Chefs de France. Also, I hear that England's fish n chips at Rose and Crown are good, but a very laid back experience.
I've not done this, but I know that the Boardwalk is a close walk from Epcot. You may want to check out some of the restaurants there.
I guess the bottom line is that if you end up at Coral Reef, I think you'll still have a nice dining experience.