Yes, the advantage that you had on the BB court vanishes when you step aboard a cruising yacht!
There are some of the modern style yachts, usually 40++ feet that boast of king-size island bunks. While these often do not make good seaberths (too wide to keep you stable when there is a lot of motion), they would give you the room and comfort you seek. But it is much less common on more traditional vessels such as the Westsail due to their smaller beams and more tapered quarters. A thorny problem for you for sure.
However, we've known a few folks (of more conventional size!) who chose to sleep on the cabin sole
when at sea, even when there were suitable seaberths available to them. Claimed there was less motion down there and so on. If that was acceptable to you, then the king size berth for calm conditions might be ok... only resorting to the sole berth (of whatever length you might wish) when at sea in rough conditions.
But I fear that you will have to look outside the Westsail 32 idiom to find those accommodations. OR be willing to drastically redesign the layout of an existing boat.
good luck with your search, mate!