i agree with you, that strength is very important for a cruiser. I`m sailing a Kennex 445 for over 15 years, once in the Indian Ocean
on the way to Oman for 4 days with 40-45 knots on the nose.....
Silver Blue's circumnavigation - Promaritim
I woudn`t do this with many others catamarans.
, i changed to Frigo-Boat system with keel
coolers, seperat kompressor/system for each box. That gives me opportunity to use one box as deepfreezer or fridge (with combi thermostat ) and the second box as fridge.
Power consuption is much less as with original system.
For isolation i used a special liquid isolation (which get hard later) to isolate also the back of the boxes, where been the biggest lost
All power, which the boat daily needs, are given usually from solarpanells, installed on a solid cockpit
roof and over the davits
I hope, i could give you some ideas, some detail photos about this you can find on Silver Blue`s webpage
in the photo
gallery under technical details.