Welcome Aboard Saturn!
I returned from the same trip just yesterday!!!! Had a blast and so will you. On both formal nights the men in my crowd wore either dark suits or pants & dark jacket, light colored shirt & of course ties.
For the most part everyone was smartly dressed on those nights; didn't notice any out-right "rebels". Some just wore shirt & tie without jackets, but they fit in just as well. Very, Very few tux's & gowns; mostly the ladies wore mid-length dresses or pant-suits appropriate for an early evening cocktail party but no one came in jeans, shorts, tee's, etc. Don't obsess over formality - just keep it "smart" and neat and most of all......HAVE A WONDERFUL CRUISE!!!!
Think before you speak......words are not connected to a retractable cord!
"Time you enjoyed wasting, was not really wasted at all" ~ John Lennon
Carnival Victory to N/E & Canada 7 days