Speakers located in Central Florida can travel to the port of departure with even less trouble. Although Miami is a huge departure point for cruise ships, a smaller, but more convenient harbor is just north.
Almost million cruise passengers sailed out of Port Canaveral in 2014. It may be hard to believe, but Port Canaveral is #3 with Port Miami at #1 and Port Everglades # 2. I would have thought Long Beach was up there, but Caribbean destinations pack them in. In 2012 and 2013 Port Canaveral was #2.
The name Canaveral harkens images of the space program based in Cape Kennedy/Canaveral. The name of some of the area honors JFK.
If you do get a speaking slot on a ship that sails out of there, plan some extra time. The Kennedy Space Center has a great Vistor Center. You may even be able to see a real launch of a satellite. The shuttle program is dead, but plenty of military missions still begin there. Nearby Patrick AFB supports operations.
Commercial companies now pay NASA to use the site and are launching resupply craft to the Space Station.