Narrowing a Backpacking Trip

I'm assuming by "backpacking trip" you mean you will carry a backpack, stay in hostels or some other indoor place, and take trains or buses between these locations. For me a backpacking trip is hiking and sleeping outdoors, covering no more than 10 miles/day.

That said, I think this schedule is way too rushed. You switch locations nearly every night and will lose a lot of time packing up (even if you travel light) and on transport from place to place. I would cut out 40% of the stops and enjoy each place a bit more, but I have kids your age, so maybe only cut out 25%?

Yes, I'll be with a travel backpack and primarily use train/buses for transportation, but I'll be hiking a few portions of the trip and attempting to camp out at certain places. I was generally thinking to take transport late at night or early in the morning to get day starts at different places, but I hear you on rushing it a bit too much. There's just so much to see! I'm okay with cutting out Orvieto and Montepulciano, combine Lucca and Pisa into half-day trips and spend a day less in Milan. But of the towns and cities mentioned, do you think I'm missing anything or that something mentioned isn't worth going to?

Whether carrying backpacks or pulling wheels, most of Rick's readers need to pack light, watch their budget, and use public transport for at least part of the trip. You need to check train or bus travel times between some of your destinations and pencil them onto your calendar. These are summarized in Rick Steves' Italy book at the end of each chapter.

To be less dependent on a Siena hub, I recommend renting a car for Tuscany if you are 21 or older (and easiest for drivers 25 or older). A 3-day car rental starts about $110, and Auto Europe also seems to have a good offer on insurance through EuropeCar. You'd have to go further through the booking process to see if a "young driver fee" is added.

Orvieto-Perugia (2 hours with 1 connection) and Assisi-Siena (4-5 hours with 1 connection) are not as well connected by train as you might have thought. Assisi-Siena is served by one direct bus, daily around 10:15, which takes only 2 hours. I have not checked the Orvieto-Perugia bus options. Instead the half-days on your plan, I would drop both Perugia and Assisi and sleep one night in Orvieto and an extra night in Siena to accommodate all the day trips.

I would also cut the big cities of Genoa and Bologna, unless you have specific things there that you want to see. Every region has good food. Give those days to your CT combos, or to Lugano or Lake Como (local public bus runs from Lugano to Menaggio).

You may enjoy Frascati and/or Tivoli, or you may find that the main sites in the city of Rome take up more of your time. I would leave those destinations optional.

How to Look Up Train Schedules and Routes Online gives you the DB train schedule link and tips for using it.

I'm bringing maybe five or six-days worth of clothes max and have a ballpark range on how much it'll cost altogether (I'm bringing extra as an emergency reserve). Fortunately by the time I'll be there, the euro should be considerably lower than the dollar, and it's about $1.06 to a euro currently.

I was looking up potential train tickets earlier in the week and noticed direct trains from Rome to Perugia that are about 2.5 hours (once in morning, once at night) and then a train from Perugia to Assisi that's about 20 minutes (and vice versa), hence why I thought I could squeeze them in. Frascati and Tivoli I thought I could do both in a day, using Rome as a hub; they seemed like nice picturesque areas.

I've heard nothing but good things about Bologna, apart it being a culinary epicenter, the Palace Tower and the Aniselli Tower looked really cool, as did Piazza Magiorre, the University and the Porticoes. But Genoa I may skip.

I think you have an amazing trip planned. As someone else mentioned you have a lot packed in and I've found it's not worth it when you just jump place to place, you'll never remember what you saw or have the time to appreciate where you are. Try to narrow it down a bit and stay at least 2 nights per place, you may see less but you'll get more out of what you do see.

While in Tuscany I highly recommend renting a car if you can, it will make it much more convenient to go between towns and you will get a lot more flexibility to see what you want and leave when you want. Perugia is a beautiful town but not a huge deal if you miss it. Montepulciano and San Gimignano are tourist trap towns but its easy to see why, they are incredible to see. There are countless other towns less travelled by tourists which are the same and you can get a more authentic visit seeing them, again why the car is invaluable.

Pisa is a huge disappointment, definitely make it a short stop just to see the tower if you must. Lucca is one of my favourites, you could definitely spend all day there, rent a bike for sure and ride the wall.

A couple days is adequate for Cinque Terre, I've been twice and can always spend longer but 2 days will give you time to see the 5 towns and maybe lay on the beach for a couple hours in Monterosso. I've never been to Genoa or Lugano. My friend spent the day in Bologna and said it wasn't necessarity worth it, the food is amazing everywhere, I wouldn't go just for food.

Just a word of caution, the Italians take their holidays the last 2 weeks in August and often many things shut down. You should be ok in the bigger cities and more tourist oriented areas but make sure you plan ahead and check that things are open, they will all be at the beach for their own holidays so keep that in mind for booking hotels and trains... otherwise have an amazing time! It's my favourite place on earth!