Agree. Vista cruises belong to a different segment: luxury, port intensive, destination oriented rather than party driven. It’s a part of Atlantis offers I’m personally looking at with great interest. (My friends who went on Marina this year, however, complained about the party component they felt was just neglected on that cruise)
Prima is twice the size of the Vista though and its itinerary does not seem to be that exciting for those looking for a destination cruise. And with more days at sea, I would expect more party activities there as well.