My DS (age 7 today!) judges all resorts by their swimming pools. Therefore, though our home resort is BWV, I think BCV would be his first choice. We have pool hopped there (before BCV opened), and DS was ecstatic. His second choice would definitely be BWV. The slide there is great for younger elementary aged kids. (The one at BCV is a little fast for the 4 - 6 year old set, IMHO.) We have stayed at WL before, and he thought the pool was beautiful, but the slide is kind of a yawn for the thrill seeking 7-year old. And, since OKW has no slide, it is definitely out of the question for young DS.
Sounds strange to evaluate a resort based upon the slides in its swimming pools, but there you have it from my boy.
As a side note, DH and I prefer BWV. BCV looks lovely, but the villas section is so far from the big pool that you kind of lose the benefit of being at Stormalong Bay. We love the ambience of BW and, of course, the location. When we've had guests, we've wished from time to time that our rooms were larger, but when it's just the three of us, a one bedroom at BWV is extremely comfortable and roomy.
Hope that helps.