The YC and BWi also have deluxe rooms. I've been investigating these. The YC's are the smallest with the BC second and the BWI's the largest. The following is from Disney Guest Services:
Disney's Beach Club Deluxe Room is a very spacious accommodation with a relaxing
view of Crescent Lake. The Deluxe Room sleeps five with two queen beds and a
day bed. These 573 sq ft rooms also have a ceiling fan, in-room safe, voice
mail, double sinks, mini-bar and concierge amenities.
Concierge Deluxe Room - 644sq
The YC is supposed to be slightly smaller than the BC's Deluxe rooms. Hope all this helps. ALSO the BWI has a queen sleeper instead of the day bed.