The playground of BW is right next to the pools and is usually wet, so unless the kids have their bathsuits on is not use. I;m not sure if at that ages the kids will actually use the playground, but at least you now know that little piece of fact.
Also, be aware that if you take the BW view, it is very noisy between 7 and 11 pm, and that can be a problem with kiddies at bedtime. Now, the convenience is that you have everything very close.
At SSR, you have to walk a lot to get anywhere, even if you are in the springs that is the closest area to the pool and restaurants, In september it rains a lot, so having the convenience of going to the store or a restaurant to eat, or even room service at the BW can work for you.