This was our seventh cruise with Carnival, the last being on the Spirit through the Panama Canal. We are a couple in our mid 40's.
We flew into Rome a few days early and stayed at a downtown B&B, the Nicolas Inn http://www.nicolasinn.com/ This place was wonderful; great rooms, helpful owners and conveniently located near the Colosseum. They arranged transportation from the airport and to the cruise terminal. We found Rome friendly and easy to walk. Lots to see and you must allow a few days to at least get an overview.
On cruise day, we arrived at the cruise terminal about 11:30 AM and walked right on. The ship is as most Carnival designs; bright and party-like. The rooms are great. Carnival continues to add conveniences and features. We loved the Seaside theater and the in-room services such as booking excursions and reviewing your sign and sail account which were time savers.