Hi Alan - not being a naval architect, I cannot speak to most of these considerations, but I bet somebody else will!
I can offer you a bit of info on a couple items.
Off setting the boards from centerline seems common to keep the trunks from being in the middle of the living spaces. The Catana
boards are placed outboard
such that the outboard
side of the trunks coincides with the outboard edge of the hulls. It seems they could be "justified" to the inboard sides as well. This also has the advantage of not having the opening for the boards right at the bottom of the hulls if the boat can be beached. I've seen some boards angled a bit off vertical athwartships apparently to make the trunks conform to the outboard angle of the hulls.
Designing the trunks to be stronger than the boards seems intuitive - sacrifice the board instead of the hull
in the event of collision
The lifting mechanisms I've seen are remarkably similar, although I certainly haven't seen them all. A line attached in some manner low on the board runs vertically up the trunk in a slot, around a block below deck
which is routed through a chase to a winch
aft. Rope clutch
to hold it up. To raise the board higher or remove it you have to lift
it from the top. Drop by gravity. The Catana
boards have holes in the bottom so they flood with water
so they won't float in the trunks.
Hope this helps,