I've stayed at Yacht Club, Beach Club, Polynesian, VAKL, BCV, OKW, and offsite at Windsor Hills. My gang has zero interest in staying on-site again (as a family--I could envision an on-sit couples-nly trip, someday).
You get twice the space for half the money, and our gang all really love it. DD16 loves having a private bedroom with a king bed, her own bathroom, TV, and wifi. We joke that, if the room had its own fridge, we'd never see her. DS14 gets his own room, private bathroom, and freevideogame and DVD rentals. DD8 and DS5 love sharing a room (they don't at home). Everyone loves, loves, LOVES the private pool.
We save a ton of money by cooking our own food. My gang doesn't like to eat out (sickos!), so we do easy-prep food. DD16 says it's not vacation without break-and-bake cookies. We only ate a few meals on property, and had a few snacks.
I will say, offsite makes it trickier to get to MK--that would be the only transportation "minus".
If I were staying onsite, I'd pick Beach Club or Polynesian. I do love those resorts. But, I'd likely do it only if it were DH and I, not with the gang. I did enjoy the DVC villas we stayed in, and, given an umlimited budget (time and money), would be interested in trying BLT. But, my gang would rather be offsite.
In the interest of full disclosure, they also like to visit Universal while we're down there. We also tend to do longer trips, less often. I mention this because we tend to relax and hang out a fair amount--the pluses of WH that I mention don't matter as much if you're planning a shorter or commando type vacation. My family doesn't do that--doesn't mean it's wrong, but I want you to understand where I'm coming from.