When choosing a reception hall, consider your guests with disabilities. Just because everyone is the picture of health when you book your hall does not mean it will remain that way for your wedding. One unexpected guest with a disability turned out to be the bride! She broke her knee just before her wedding day. Sadly, there are many places that are not very accessible. It is not fun for a guest to sit alone in the reception room upstairs just because the cocktail hour is down a flight of stairs. Or for guests that cannot make their way to the reception room at all. The only way into the Old Mansion in Elizabeth, which no longer exists, was up a staircase. And if you needed the restroom--more stairs. Believe it or not, there are still reception hall rooms out there that are not accessible.
Some halls do have access between the floors by going outside and walking around the building. But again, sometimes the walk is just as hard as doing the stairs. Especially in bad weather.
Also consider the location of the restrooms. Is there one nearby for guests who cannot go "over the river and through the woods" to the other side of the reception hall? As an example, the large ballroom at the Richfield Regency in Verona has its restrooms down a flight of stairs. But an additional restroom is located on the same level as the ballroom for guests unable to use the stairs.
Bottom line, do not assume a reception hall has easy access to rooms or restrooms. You really need to ask.