New York to Southampton on QM2 is a fantastic experience. I can vouch for what others have said about the Cunard liners being built to smooth the effect of rough seas. Back in the 1970s I sailed that route on the old Queen Elizabeth II, and have a distinct memory of eating breakfast in the main dining room and watching waves climb high onto the big windows of the room.
It took me more than three decades after that to make another crossing on the QM2, and even in Standard class instead of the higher Grill booking classes, it's a premium quality experience. Hope you get a chance to enjoy. A fair number of my musings about travel when I retire always circle back to that kind of sailing.