I've always wanted to try Polynesian. But as our last two trips have just been my wife and I (kids are all out of house now) we've opted for Beach Club and now Boardwalk because we really enjoy the food at Epcot and it's just so easy, plus you have the skyliner/boats to get to Hollywood fast.
We've stayed at:
Grand Floridian Villas, Beach Club Villas, Contemporary, Kidani Villas, Riviera and are now booked for Boardwalk Villas.
For location and the parks we generally go to Beach club so far has been our favorite. We loved Grand Floridian with the kids and Kidani with the kids was great, but those halls are loooooooooooooooooong and the transportation is pretty limited (buses only). I really wish they'd work out something to get another skyliner route or something over there.
Riviera was nice but felt a bit by itself.