The Grotto pool and beach area are coll also at the S/D.....AND the Boardwalk is right there....we LOVE the Boardwalk bakery and being able to see most of Illuminations from the S/D doesn't hurt either ...in case your little one is tired and you would like to be near your room instead of in the park to watch it. We always ride the boat for leisure as well, and you can go over to the Yacht Club marina and rent different watercraft, we like the mouseboats, or (sea racers I guess they are now) I know you may be at MK a lot with a 4 year old, but being able to walk or quick boat ride back from 2 parks for a rest is huge to me....and you also have many resturant choices close by between WS at Epcot, Boardwalk, MGM and of course the resorts all around Crescent lake, BC, YC, & S/D. Even tho S/D has busses, you can also walk/boat to MGM to catch a bus there to another park from MGM or the same to get thru Epcot to the monorail. While the S/D is a large resort, just ask to be in a room closer to the elevators. The Swan is a smaller building, but laundry and most restaurants arein the Dolphin, including 24 hour Tubbi's...or has the name changed?
We have never stayed at POFQ, and the slide looks fun and the grounds look beautiful, and easy access to DTD, but I think the S/D falls more under deluxe than mod. We went one year and stayed 3 nights at the Dolphin and did not set foot into the parks. ( not that we didn't WANT to, but a quick stop over to visit family and on a TIGHT budget)There is Fantasia mini golf right there, boat rental, the pool , we visited other resorts to check them out and hit DTD, free petting zoo at Fort Wilderness. The S/D also offers the refil mugs like WDW resorts. I think the food is higher priced at the S/D, and then there is the daily parking fee if you have a car which is a bummer. Those are my negatives, other than that, we have always enjoyed our stays there.
Pam