Hoboken or Jersey City Help
I would recommend Amanda's in Hoboken. It is in a lovely townhouse with a few beautifully decorated rooms of different sizes. The food is delicious and presented elegantly on eclectic china plates. The service is always impeccable. I think this would make a great spot for a special rehearsal dinner (I can vouch for it personally as we had our wedding dinner party there :) ) .
I'd second Amanda's. We had a business dinner there last week for about 20 people. They created a private setting for us by closing the curtains across the doorway in the room we were in and the service was great, which you don't often get with a group that large. There was a set menu but they were very accommodating for some vegetarians in the group. Also might want to try The Brass Rail, lower down on Washington Street. They have a room upstairs (not sure if it's big enough for 50-60 people, though) that would make it private. I've found service there to be quite good for large groups too. Food is pretty good (Amanda's was better).