A guy at work stayed on the third floor and took great pictures from the room ( w/ balcony?). I think the room was facing away from the lights at night or should I say far left side of the Front face when facing the slopes.
Not sure if the first floor is more noisy with sounds from the crowds or the snowguns.
I would go for third floor or higher. I like the snow scenery more than people watching but that's me.