"If Paradise were a huge success, surely Carnival (and other cruiselines) would have built more such ships."
A premium cruise line that bases a nice, relatively new, desirable ship with excellent cuisine and service that is (at least occasionally) totally non-smoking out of the San Francisco Bay Area or Los Angeles or San Diego has a very good chance of success, in my opinion.
I have no interest in booking a Caribbean cruise with any line, let alone Carnival, but would be happy to cruise frequently from California on a fine ship that has at least very restrictive smoking.
One good ship. That's all. One.
Am I going to get flamed for this?