Traveling light
Everyone says to travel light. We did it well on a 14 day trip to Japan using only one backpack/suitcase each and one daytrip bag. How'd we do it?  We used the Rick Steves' Convertible Carry-On. It's bigger than you think, and loaded with useful features. Pockets, laundry bags, zippers, compression straps. It converts to a back pack or a normal bag. Lots of expandability. Held up beautifully, on airlines, trains, and ferries. See travelstore.ricksteves.com
Disclaimer: I don't work for them or have any interest in the company. I am just a big fan. Everyone in our group was jealous of our small bags!!