I agree that it depends upon the size of the cat, but also upon her intended use. On cats below 40 feet, a galley up will inevitably have less counter space, less
storage space and will virtually eliminate the possibility of a full-sized chart table/nav station with a proper seat near the
companionway. It will also often lead to a galley that does not have proper bracing for use while underway in heavy conditions.
If you do not
liveaboard or plan on making extended passages, then these will matter much less than the ease of access to the
cockpit that makes daysailing/entertaining so much nicer with a galley-up: while it is possible to have a galley-down that is open to the main
saloon, I have yet to see one that has direct access to the
cockpit.
Of course, once a cat gets to be about 45 feet
LOA or above, it is possible to have both a well-braced (U-shaped) galley with adequate counter and storage space, as well as a proper sit-down, full-sized chart table/nav station in the bridgedeck accomodation. At that point the principle arguments in favour of a galley-down are reduced, although they still keep the most heavy part of the accomodation and stores lower in the
boat, thereby reducing its Cg.
In a larger cat, IMO a galley-down still makes better use of the 'tunnel' shape in the hulls than the commonly installed 'sofa facing a wall' that is included in the owner's
cabin of many cats of that size. Afterall, why do many people like 'galley kitchens' in apartments? A small floor area surrounded by counters and cupboards on both sides is a very efficient use of space.
Looked at in another way - if I wanted an additional sofa/settee in my boat, I would want it in the main
saloon.
Brad