Other things to consider... Marriott has probably the best elevator availability of the three biggies. The Hyatt's main tower is notorious for never having an elevator/one with room on it. If you go for the Hyatt, I'd recommend the International Tower, if you can. I'm not a fan of the Hilton or Marriott, or the main tower of the Hyatt, because of my vertigo. Glass elevators and I don't get along tremendously well.
I tend to not be a drinker in general, and have never been drunk in my life, so such factors aren't a concern for me. I usually stay at one of the hotels only a few blocks away, as the walk isn't a killer, even in costume, and it's close enough that I don't get (many) odd looks. I'd like to stay in one of the host hotels -- my first pick would be th eHyatt's International Tower, but price and -- to a lesser degree -- availability have always been an issue. Room-packing is about the only way I could afford it, and I tend to prefer not doing that. I try to keep it to four for a room, six for a suite, and at the Hyatt's prices, it's still a major chunk of change for the five or six days I'd be there.
--Jonah