One suggestion: take the room parties out of the guest rooms and penthouse parlors, and put them on the ground and mezzanine levels of the convention center and hotels. Abled-bodied members can walk a flight or two of stairs and save the elevators for those who need them to go up or down a level.

London in 2014's planning to have the parties at the convention center, but that does mean changes for how you use space in the evening, and negotiations over catering. But we're Fandom and we know how to negotiate hotel contracts.