Personally I don't think a museum would work so well. It will most likely be much larger than the hotel, and some characters will get lost. In a smaller museum we would most likely get bored quickly, and leave to investigate the surrounding area. Then newer people would be confused as to why it is called Character Museum when we are obviously in Little Italy.
A beach house would not be too bad, but there are some things that would need to be explained. Namely how all these strangers who could be at odds with each other are in the same beach house. Also what else is there to do besides talk in a beach house.
I may be a bit biased (Eagle Scout and nature lover) but I think hiking mountain trails may be the best option. Sure it is really open ended, but we could expand on the area at our own pace. Also I think it could fit a wider range of characters, as long as they don't detest greenery.
Plus I think it would be a nice change of environment from the usual mostly indoor/city threads, that is as long as there aren't any dogs planning on nuking a city park and getting away in a blimp.
All in all I am willing to go with whatever you guys decide.
Though we could have a beach house next to a nature museum that has a trail leading into the mountains. However that is just insane.
Has ADD, plays World of Tanks, thinks up crazy ideas like children making spaceships for Hitler. Occasionally writes them down.