Several come to mind.
Victoria Falls, although it can get very noisy when Boma is packed.
Mizners at the GF is wonderfully elegant.
The Bellevue Room at the BWI is quiet and a great place to watch a torrential rain outside.
Martha's Vineyard at the BC, relaxing and seldom if ever crowded, one of our favorites.
If you're a wine drinker, and it's not crowded (yes, this does happen now and then) the bar at the CG is wonderful.
Anne