I've only been on 8 cruises (all on Carnival) and have encountered nothing close to anything I'd consider "rowdy" enough to warrant a fine or disembarkation. Lucky me, I guess.
We're staying at the Marriott Courtyard downtown in December. When you're going makes all the difference in price, imo.
She said there's a 3rd party shuttle that'll take us to the port for $10pp, or we may just call a cab.
We have a later flight leaving Miami in December ... we opted for an excursion that takes us off the ship, sightseeing, then to MIA. Maybe that'd be an option to kill some time?
We had a lot of fun ... they had activities all week as well as a costume parade/contest - people really go all-out. We're hoping to book on next year's Halloween cruise on the Vista.