A vote for Yak n' Yeti.
We liked it so much, we ate there twice on our last trip. The shrimp and steak for entree and the cream cheese wontons for dessert...mmmmmmm.
Rainforest is not bad but, not part of the dining plan, and we have eaten there in other places, so we skip it most of the time while at Disney.
Tusker House is a buffet, so in a different category in my thoughts.