If you like days at sea and want to drive instead of fly to the embarkation port, the New Jersey departures are great. The first two and last two days of the cruise are at-sea days, with all the port stops together in the middle of the cruise.
If you don't mind flying (both the expense and the experience) and want a shorter cruise, the Florida ships are varied, with many that are bigger or smaller, and newer than Explorer of the Seas. Depending on the itinerary, you'll still have days at sea and port days. There are just a lot more ships from which to choose if you leave from Florida. Your travel agent should be well equipped to help you with your decision, depending on your wish-list for this vacation.
Also, depending on your travel dates, there are ships that leave right from Baltimore on both Royal Caribbean and Celebrity (among others). Those itineraries include Bermuda cruises, New England/Canada cruises, and 9-11 day Caribbean cruises, again, depending on time of year. It's a great option for folks within driving distance.