Consistency in Design

We’re interested in the concept of ‘consistency’ with regard to current design thinking. The following images are from a 1930’s cruise liner, and they help to raise some interesing questions on the subject. Is the cruise liner carrying any ‘styles’ or ‘fashions’ from the era? Or is it’s form a consistent following of the machine’s function? Is the ship’s aesthetic -funnels, portholes, handrails, lines of structure- a pure and consistently derived from functional requirements in the design of an efficient machine? Or does the design have other leanings towards ornament?