WOW! This one really caught my attention.
My response: well, romance and sex on board is alot like romance and sex on land. Some folks (i did not say 'women') want and need alot of luxury and a non-moving floor. Other folks (I did not say 'women') like it in a tent, in the park, or in a car. As for some folks (I did not say 'men') they just need any place to have sex.......so, know who you are with and make the best of what is in front of you!
P.S. If the kids are very little.....you only need a little space of separation....the older they get, the more space you need. Once they are 10 or older....best to have a locked door or take the dinghy out to that deserted island! When there are NO kids aboard....then any stern or bow topsides or below will do!