I went to a bat mitzvah at Leonard's of Great Neck, and I thought I would post my thoughts on that event, as they might pertain to a wedding.
The family had booked the Holiday room on the second floor for 180 guests. The room was set up beautifully! The space on the dance floor was a little tight, but since there were so many pre-teens, teens dancing and running around, it might be okay for a wedding.
The food was good--not superb, but good. Service was pleasant, though the servers did not come around enough. We ran out of water at our table, and also had trouble getting seconds for coffee. The Viennese dessert table was unbelievable though--they put out such a huge amount of food.
Overall, it was very nice. Other than the service gaps, I didn't see anything wrong.