Stormalong Bay is widely accepted as the "best pool" due to the lazy river, sand beach etc. But it is also one of the coldest ones in chilly weather because it is so big, it is harder to keep warm. It also is not the best for little kids as it has a lot of deeper areas and is very spread out.
Honestly, all of the deluxe resorts have very nice pools, with water slides and nice landscaping. The Poly Volcano pool is excellent. GF's pool has a waterfall and a view of the monorail going by. At the moderate level, CBR and Coronado have cool themes but lose points in my tally because they get more crowded with the large number of resort guests, and since you mention heated pools, that looooong walk back to the room at the moderates when you are cold and damp aint fun in colder weather.