Ventilation and insulation
don't conflict except in the fact that you have to draw dry cold air in to displace hot moist air. Very necessary, as it is in a house.
will stop a lot of the condensation
that you are going to be battling daily. You must keep the air circulating constantly in all cabins and cabinets. Good fans are a must. Either a good diesel
fired forced air heating
system or diesel hydronic heating system will help although you can get by with a ventilated diesel stove and a good fan to circulate the heat. A diesel stove makes it more difficult to heat other cabins.
Computer fans mounted in the bulkheads of closets will help keep your cloths dry. There must be a vent for inlet air with the fan blowing out. Make sure the hull
is insulated in closets or your cloths will get wet and moldy. Insulate your hatches.
Hatches and Port-lights will get wet with condensation.
What else do you need to know?