I LOVE black so that's the number one reason I travel with a lot of it. But a close second reason is that it's very forgiving as to stains. If I "dribble" food or wine, it doesn't show. Also it's versatile. You can throw practically any scarf, jacket, vest, etc. on with it and have a new outfit.
I found out the ultimate advantage to wearing a bright color on formal night - easy to find your pics on the wall. I wore red and I could spot us among all the others easily. Mostly just dress to please yourself - if you feel good you look good - have a great cruise - TTFN Jennifer