I have over 25 years of packing light and traveling to Europe experience...take less, do laundry...there are many stylish quick drying fabrics these days...
I travel to France and Italy frequently....mostly with 22" and a tote bag for Paris, because I stay put in one place...Many people will tell you ONE bag...but if it weighs 25lbs how are you going to lug that around and lift it up stairs, onto racks buses etc? Even light 22" cases weight 7lbs.... Most people bring a daybag anyway so why not pack your items in it on the travel days, and empty it out at the hotel to use as your day pack...if you don't want to pack an another small folding bag.
In Italy I traveled by train, ferry, bus and car...and trains I took these 2 bags to Rome, Naples, islands last fall for a 2 week trip...with a travel bungee...for rolling long distances or in HOT weather where I did not want anything on my back....I also packed a small purse, and thin folding nylon shoulder bag...like a nice grocery bag that could not be reached into...
Travelon 15" ( 15" X 13" X 9") two wheeled roller/spinners do not work on cobblestones and take up too much space that could be used for clothing. This is only 7 inches less than a 22" bag because the larger bag has 3-4 inches of height taken up by spinner WHEELS.
https://www.amazon.com/dp/B00ICD65CO?tag=amz-mkt-chr-us
The handle extends nicely and is sturdy...it zips into a compartment when you don't need it.
You can google videos that show how much you can fit!
The interior has tons of space and can be packed with or without cubes. I put my ipad in the inside pocket not the outside one for extra padding and security. It is SO easy to lift up because you will probably only pack 10 lbs in it and it is only 5lbs.
I fit over 25 clothing items including 1 pair shoes, 1 flip flop, 1 shorts, 1 jeans, 2 cotton pants, 8 shirts, 1 sweater, rain poncho, my TSA 3 1 1 liquids, bathing suit, cover up, sarong, socks underwear, electronics like ipad charger, small camera, guide book, you get the idea...then the back pack was only 1/3 full. Inside the backpack I had a mini backpack( that I wore on my chest/front) while in crowds in Rome and Naples, you will see Europeans doing this.
I took this, but is has stiff shape and you may prefer a soft, more flexible style.
https://www.ebags.com/product/osprey/porter-30-travel-backpack
I packed this inside my larger backpack and used it as a day bag
http://www.eddiebauer.com/product/stowaway-20l-packable-pack
Travel bungee cord amazing! For longer distances or when hot you can put the backpack on the top of the bag!
https://www.ebags.com/product/travelon/bag-bungee-two-pack/3
Take the RS travel precautions seriously, but don't worry...petty crime is the most you will have to be aware of...definitely keep your passport ON YOU at all times, not in the hotel, use an under clothing pouch..there are many styles...There are many travel shirts that have hidden pockets at the HIP not the chest so they are less obvious and bulky looking...
I use this for my daily cash and one credit card...just attach to ONE bra strap and tuck into side of bra...you won't feel it and it is the ultimate in security! You will need to put passport and other things in a larger pouch.
https://www.amazon.com/Security-Pocket-Brastash-Credit-Sleeve/