with toddler thru 9yo(ish), i would vote BC - the pool and character meals being the big draws. some BC balconies ae SRO, as pp noted.
with pre-teen, teens, and adults, BWI/BWV. entertainment is right downstairs, and views are amazing. we find these resorts quieter (BC/BCV tends to have more little kids, lots of noise, and a more chaotic feel). all balconies are full.
EPCOT close to both (at BC, it takes longer to walk to the lobby, then down the lonnnnng walkway; at BWI, it is a short walk to the BW, then maybe a minute of walking along the BW itself), and DHS about a 15-20 min stroll. mini-golf is nearby.
i think one of my favorite things about the BWI/BWV (besides BW view, of course

), is that there are so many options: nighttime entertainment, jellyrolls, dining on the BW (love sitting outside BRG), surrey bikes, belle vue lounge....and we're just minutes from our room. the quiet options are fantastic: reading on the back balcony, the stunning (and QUIET!

) BWI pool, simply strolling because you feel like it........