One restaurant that is often overlooked, but is a great deal, as well as NEVER being busy is the Marrakesh in Morrocco. The food is really good - not too exotic at all, the desserts are wonderful, the belly dancer is very cool and the servers have to be some of the nicest at WDW. The mint tea is so soothing. I could drink it all night. There’s never a problem getting a PS and the restaurant is really beautiful. My absolute favourite at Epcot is LeCellier - but if you walk over to the Boardwalk, Spoodles is a very good choice too.
The Cape May Cafe at the Beach Club is good too, if you’re looking for a buffet.
For a quick lunch - (I know, we’re doing sit-down restaurants) - but do not miss the Earl of Sandwich. Soooo gooood!