I am curious why you didn't consider the Grand Floridian? Such a wonderful resort!
Personally I would stay in an Epcot resort if I was doing mainly Epcot and MK. You always feel to be so privelged to be one of the lucky people who can go in and out of Epcot at will and not have to take the monorail or bus back to your hotal. We adore Epcot and the Epcot area. The restaurants the boats, the dueling piano bar, the dance hall, etc.This would be so much fun for a couple to experience. It is so wonderful to be able to walk around the BW, BC,YC area at night AHHHHHHHHHHH! The BoardwalK area is FABULOUS! I would suggest the Boardwalk Inn Concierge or Yacht Club concierge.
Poly lagoon concierge is great but a change is nice too since you just stayed there.
Have a wonderful time but think about trying the Epcot resorts next time.