No question in my mind. If airfare isn't a concern, then the only choice would be the southern cruise. We have done a southern cruise aboard the Grandeur and departing from San Juan was a breeze. Arrived a day early, spent the night at the Marriot which was very nice, then a quick taxi ride to the ship. Got there early, the boarding time was given as 2:00 but we got there at a little after 12:00 and walked right thru the check in. We were on the ship in 15 minutes from the time we got out of the taxi. It was fun seeing all those Carnival people waiting in line OUTSIDE their terminal building while we were walking right into the nice RCI airconditioned terminal. Did I mention it was sunny and hot that day? Once thru the check in and the photos we went to our cabin. Just before getting on the boarding gangway we saw some stores, so after dropping the bags off at the cabin, we went back to see what was there. Not really much interested me, except the liquor store. I don't/can't drink, but lots of other people looked like they could. They just bought it and carried aboard. There was no one checking. We bought so sodas for the cabin fridge.
To sum it up: San Juan is a recommended departure port.