Now this may sound a bit off the wall, but  I would like to suggest an idea for experiment. Maybe it's been done already.

In 1998, I sailed on the Australian museum ship, Endeavour, from Halifax to Bermuda. At night we slept in hammocks strung from the deck-head at 45 degrees to the center-line. It was miraculous. No matter if the ship rolled. pitched or yawed, the hammock moved enough to dampen the movement. It was very comfortable.

I was thinking that if there is enough room to string a hammock in a sailboat's saloon, it would give the off-watch person better rest during an ocean passage.

Has anyone tried this?