A lot of good options above. For me it comes down to whether you consider just the resort or the area it gives access to.
If including area, Saratoga for access to Disney springs is good option as is the beach/yacht for access to epcot (though this may not fit your idea for break from parks). Resorts on monorail also give access to lots of great options.
If only looking at resort itself and evaluating in terms of relaxing on break from parks I would likely lean towards wilderness lodge just from my personal taste of relaxing. This has great causal options with whispering canyon, geyeser point, roaring fork. My second option would be contemporary which I feel has great dining options but not what I think of as relaxing break from parks (wave could be but chef mickey and California grill seem like bigger events to me).
That said, I have trip coming in January and from my side I picked beach/boardwalk for part and bay lake tower for part. Beach club gives easy access to festival at Epcot which is one of my favorite ways to dine (enabled by park hopperretuning). Bay lake tower is for second half mainly for proximity to MK but we have access to tons of optios across contemporary, grand Floridian, and poly.