We humans like to celebrate occasions by decorating vessels and now commonly use strings of lights instead of strings of signal flags.
On one July 4th, our crew surprised us with a beautiful combination of string, spot and mood lights on the flybridge and boat deck. When I congratulated the captain, he advised that we could have such special treatment more often if we carried more crew. That 40m vessel could bunk only six in crew, so I agreed that we could have even more lights and have them more often if we moved up to a 50m.
As it turned out, we were not truly denied sufficient lighting on the 40m because a subsequent crew member was a serious devotee of almost every conceivable use of decorative lights, the frequent use of which soon cured my desire for the famed 50m lighting.
The inner and outer appearance of most large yachts has been the work of serious and well known designers and decorators, so both the usual interior and exterior lights work well. An occasional change for special occasions can be pleasant because of the novelty, but novelty should be rare so as to be novel. It might not be clear from old paintings, but vessels were rarely dressed since those signal flags were on board for an entirely different purpose.
Different strokes for different folks and some charter guests love a series of novelties, but it is useful to remember that repeat guests and private owners rarely decorate their homes with a variety of light strings or signal flags.