If not visiting the parks at all, I'd rather go stay at a high-end beach resort with stunning ocean views, even better (and less crowded) pools, nice dinners, and stronger less sugary cocktails for the price you pay at Disney. I'm about as big a WDW fan as you get, and even I have to admit that the food, drink, and lodging at Disney World is overpriced for what it is compared to other destinations because of the parks access.
It sounds like you would actually enjoy a
Disney cruise. The food is very nice and included in the cruise price, there are lots of fun disney touches, and
castaway cay is gorgeous. Nice spa too. If you have kids, they'll get to enjoy the kids clubs, and if not, there are sections of the ship (pools, bars, specialty restaurants) that are adults only.
Now if you're a DVC member staying on points so the room is already paid for, I'd for sure say go for it, although even then, I'd lean toward Hilton Head/Vero Beach or Aulani to avoid the crowds you get at WDW area resorts.