We've been to the BC, AKL, SSR and the Swan, and the Swan pool was our favorite -- the waterfall is so much fun! And as a mom I really appreciate that you can see the slide and the steps leading to it from the same place.
If you have young children, the fact that there are lounge chairs completely covered by the rock overhang (e.g. no sunburn) is nice too and it was never crowded.
We liked Stormalong Bay too, but it's exhausting to watch your kids there and always crowded! Also the BC costs way more than the Swan. We also liked SSR, but weren't wowed by it. The pool at AKL was too crowded the whole time we were there.