(I went to Italy with my college, I got lost, by myself, in every city we went to and survived. Some lesson's learnd that might help in planning for your Med cruise.)
Italy:
Their ice cream is lovely. Eat lots.
Mostly people in the tourist places speak English. Pointing, drawing pictures, works also. Picking up enough Italian to be able to order off a menu is priceless.
They think of meals as social time so they take a long time.
Don't drink tap water.
Rome:
Reminded me of New York but with Roman ruins, most western of the cities we went to. Wandering around the forum, Circus Maximus, Capitaline Hill is fun and simple to do sans tour. Some great fountains and squares to expriance / photograph.
For the Vatican:
Do not think about planing to take pictures in the Sistine Chappel! The company who paid for the restoration, owns the film rights to the frescos and really it is too dark to shoot them with out a comercial lighting rig. And the guards find you and throw you out. Happened to a friend of mine so I didn't even think about trying when I went.
Instead I tried to take pictures in stairwells of the nifty carvings and got yelled at. They really don't want you taking pictures inside.
Interior coat pockets are wonderful. I had this jacket with large pockets. Fit my pasport, cards, money, water bottle, maps, camera, notebook with room for postcards, and gifts!
Yes Italy has pickpockets. Be on the look out!
Florence:
Lots of wonderful shopping! Nice places on the Ponte Vecchio but you need time to haggle! I bought a lovely gold bracelet that they cut down to fit. There is a market with a boar that is better for quick shopping and you can start a bidding war pretty easily between vendors. Bought this amazing leather breifcase, scarfs, ties, a wallet, and a marble leaning tower of Piza.
Also some amazing churches! The Duomo and is great and also provides a good landmark when getting lost! Much of the city is on a grid plan so it is easy to get around.