To understand what lays ahead of any naval architect or even a boat designer, take a look at the Design Process Representation. And to make things a little more complicated here is a quote from "Introduction to Naval Architecture" by Thomas C. Gillmer and Bruce Johnson:
2. Machinery and propulsion
4. Command and controls
5. Auxiliary system
6. Outfit and furnishings
The interfaces and interplay among these subsystems must be identified and defined.
The secondary subsystems in each must then be defined by more detailed functional blocks. Components for emergency operation and casualty procedures must be provided, and in the design stages particularly, prime considerations must be given to weight and buoyancy, speed, power and endurance, volume relationships, payload capacity, general arrangements and habitability, ship-motion effects, and acoustic influences.
All ships are systems, but the integration of their subsystems varies, by the degree of integration. The measure of this degree is found in the science of systems effectiveness. The designer should expose his/her ship's system design to this orderly evaluation procedure.
Integration of these multiple considerations is generally accomplished before the actual preliminary design is begun. Systems integration ia a goal to be achieved insofar as economics allow, demands require, and skills of the designers and builders enable."