When you say you've only been to Italy in the South, it's not clear to me where you have been. Some people would interpret that as not having been north of Naples. Not to sound picky, but when you say you want to head south to Cinque Terre, I'm thinking that's in the North. At least to me, it is confusing.

When you say a trip to Milan, hopefully it only means where you are arriving and departing from. Milan is not one of the most desirable cities to visit in Italy.

Lake Como in May is pretty heavenly. However, it is a huge lake. You really don't go to Lake Como, you pick one of the cities on the Lake, and that's where you go. If you are in Varenna or Bellagio and get a place with a lake view, when you wake up and look out the window, it's an, "oh my gosh," experience. And you realize why houses there almost never go on sale. They just keep on getting passed down for centuries. No one would ever want to leave.

You only have 14 days. You will want to at least visit three cities on the Lake, and hopefully spend at least a few days just having two hour lunches, sitting on a bench near the water, and wandering around. I don't see how it is possible to experience Lake Como in less than five days.

Cinque Terre means five lands. It's five separate towns. I'm not sure that you need to visit them all, but you probably at least want to visit three or four of them, plus spend a day or two just relaxing instead of traveling. Now you are at eight or nine days.

With two weeks, you really shouldn't go all the way to Italy just to travel with a map, ticking off sites to see from a guide book, and going from city to city. It's an experience. Smell the foreign smells, taste the foreign food, talk with locals. Get to know the rhythms of the city or area. It's more about the experience, and not about the number of cities you can squeeze into two weeks.

When I hear Lake Como, Stresa, Lugano, Venice, Siena, Milan, Ravenna, all mentioned in a two week trip it sounds nerve wracking. I know you don't plan to go to all of those places, but it's going to take close to 10 days to experience Bellagio or Varenna plus the Cinque Terre, unless traveling means going to a city, grabbing a bad sandwich, ticking off sites, collapsing in a hotel at night, then traveling to another city and doing the same thing the next day. It's the opposite of what Lake Como and Cinque Terre are there for.

I don't think that anyone should go to Italy and not spend a week or so in Venice, but, late May would be challenging. It can be so crowded. If you are going to go there I would squeeze it into the earliest part of the trip because it just gets worse as you get closer to summer. Even in August you can breath in Varenna. In Venice, you cannot. It's not bearable. I wouldn't go there even for free in August, but you can do it in early May. Cinque Terre also get dicey close to summer.

If you haven't been to that area of Italy I don't see the point in considering Ravenna. Italy is sort of small, so things aren't really far, but Siena, Venice, Como is a stretch in two weeks.

I would encourage you to choose an area, and focus on it. You shouldn't really move from town to town in just two weeks in Italy unless you want to just sightsee and not experience it, not sense it. A week at a quaint town on Lake Como can change your perspective on life. A day or two there cannot.

As for driving. There is no problem driving. But there is no point in it. You can't really use a car in Bellagio or Varenna. You can't have a car in Venice. You can't bring a car into Siena, you have to park outside and walk in. Only two towns in Cinque Terre have a place for a car. Trains and ferries work just fine. A car is just a pain for what you are planning.