The arrival is not too bad, I too like to arrive the day before to avoid stress but as long as the airline stays close to on-time, it’s about 30-45 minutes to deplane and pick up checked luggage and about a 45 minute taxi ride (Around $45) to the sea port. Allow 5-10 minutes to get a car or shuttle. You can go online ( http://www.floridalimo.com/
) and have a private car driver ($70) waiting for you at the luggage carousels. Or arrange a ride in advanced on their shuttle ($21 / person). Boarding usually closes about 3:30pm for a 5:00 departure.
Making a 10:30 flight out of Miami is unlikely. You need to be at the airport by 9:30 to check bags and work your way through security. If seen the Miami port take until 8:30 or 9:00 to clear the ship, then you still have to go through customs. If none of the later flights work can you add a day to your trip and return the next morning?