This was our honeymoon cruise. What drew us to it was the itinerary: Rome, Messina (Sicily), Athens, Ephesus, Turkey, and Crete. I had only ever been on a Princess cruise before, but RCI was rated so highly, it was a no brainer.
My husband and I got into Rome the day before. I know passable conversational Italian, which saved us money on our cab ride to our hotel (make sure you know common rates before or they will rip you off). On our own, we headed to the Vatican and Colosseum. The next day, we took the metro and then a train to Civitavecchia. You will likely be able to split a cab with others heading to your port; it's a very short ride (10 minutes).
Embarkation was very easy. Our bags came fairly quickly and we had a nice meal in the meantime. Not too much else to report on that.