I wish I could travel with just a carry-on! My husband does for business, but he wears a business suit all week and his company pays for his other clothes to be laundered.
When I pack for WDW stuff just seems to multiply as I set it aside to be packed. We usually end up with 1 regular bag each (22"-24"), plus 1 backpack, plus 1 electronics bag, plus stroller bag, plus car seat bag which doubles as the "bag of all sins" that holds last minute additions. And I still do laundry part way through! **sigh**