Location, location, location!
Though we're not (yet)
DVC members, we've stayed throughout the Disney property (all monorail resorts, Fort Wilderness, most EPCOT resorts), and you can't beat the location of the BCV or BWV. Being able to walk to two parks is incredibly convenient. In terms of "pull," there's no question that BCV and BWV top OKW for our family of full-grown (if not always mature) adults.
I considered OKW as well, but one thing I've learned from reading these boards is to buy where you want to stay. If you have to vacation during peak periods, the 11 month booking window at your home resort will certainly give you an edge. And while a BCV home resort will not preclude you from staying at OKW during peak periods, the opposite may or may not hold true.
By definition, ALL Disney resorts are kid-friendly. If you are seriously planning to buy resale, be sure you consider the long haul, and how your particular needs will change over time. Space may seem critical at one point, the pool facilities another (in which case SAB is top notch), and convenient location yet another.
Few people buy into DVC looking for a return on investment, but properties become available for resale as family situations change over the years, and OKW has been around the longest. BCV is less available, and you know what they say about supply and demand.
IMHO, if you have the means and opportunity to buy into BCV, do it. You won't be sorry.