I stayed with my adult daughter at BC and we loved it. Our only room request was a full balcony and we got it.
I agree, people say BC is not as quiet, because of the very popular Cape May off the lobby, but how much time are you spending in the lobby
it wasn't a problem for us.
Another perk of BC is that the Marketplace is there, it's the resort store and also has the counter service, that is shared with YC.
We are going to try YC in August. Both are great resorts, and we are looking forward to returning in August.
What I really like about bc/YC is that everything is under 1 roof. So if its raining out, you don't have to gear up just to grab a bite to eat, or refill your mug.
We've also stayed at Poly, WL & AKL. And enjoyed them all. Poly has the largest rooms, and the grounds are beautiful. Also good transportation with monorail or boat to MK, and walking distance to TTC for Epcot.
WL is all under 1 roof too, and fun boat to MK. Rooms are smaller. Another beautiful. Resort.
AKL has same size rooms as WL, and animals.
If you are sharing a room with your parents, I'd stick with either BC/YC, or go to Poly with larger room. With Poly you will run the chance of no balcony in some longhouses 2 nd floor rooms don't have them. Again, we put it in our request and had one.
I think WL & AKL rooms which are the smallest of the deluxe may be too tight for 4 adults. Bc/YC room size would be in the middle.
Have fun planning!