Re: Trying another tack... Looking for the right boat near Vancouver, BC.
If the deck has the proper camber and isn't pushed down it is good as is. I would make a new stronger beam that fits the existing strange curve below to eliminate any future deck compression.
If you paint the new beam to match the overhead the flat will be less visible.
You don't want a keel stepped mast - that would require way too many changes.
Living aboard in Victoria Harbour