As others have said.. 1 day in Rome won't cut the mustard lol. Our first cruise over there, we made sure to start and finish in different ports. It ended in Rome and then we had 3 nights there before flying home. That was 'just' enough to squeeze in quite a few of the major things. We started in Athens and went to Santorini day 2. Funnily enough, we're going back June 2023. I would recommend stacking a few cruises against each other and see what has the most of your 'must see' ports. You won't get them all in one go and will need to sacrifice some.