I made the mistake this year of waiting to book all of our 7 days for Dec. 3 - 10 at the 11 month mark of checkout. We did not get 2 of the days. We were on the waitlist until just recently and finally decided to just split our stay between a standard view and BW view room. SO-O-O, just be sure to call day by day for your ressie when it is at a busy time.
We have stayed in lots of BW view rooms and all have been good. If anything, the rooms farthest from the elevators may have a slightly better view of Epcot fireworks. Higher floors may also be a tiny bit better fireworks view. But the differences are so slight that it is not worth worrying about.
Hope you like BW view as much as we do. For us it is definitely worth the extra points. When I am having tough times I escape mentally to a cup of coffee early in the morning on my BW view balcony, watching an illuminated Spaceship Earth in the brightening sky and listening for the sound of the first Friendship boats coming to take happy families to MGM and Epcot. My idea of serenity!