I consider the whole "loop" the Boardwalk! It's no big deal to walk from YC/BC to the BW, IMHO. We do it a hundred times a day, lol!
I have teen boys, 15 and 17. They LOVE Stormalong Bay. So much, as a matter of fact, that we sold the 180 points we had at OKW and bought 200 at BCV (we now own at BWV and BCV).
The pool can't be beat. You can rent tubes or, even better, Noodles and just float for hours! My boys always manage to meet other teens (girls, of course!) either in that pool or the HUGE arcade, which is right off the pool.
I would say to go with the BCV. That way, you can enjoy SAB, and have the option to pool hop over to BWV. The arcade is great for kids, as well as Beaches and Cream, which is a "soda fountain" type of retaurant, that serves GREAT burgers, and, of course, ice cream!
My vote is DEFINITELY for BCV. Newer rooms, SAB, and only 5 minute walk to BW, where the "action" is!!!!