I have brought just a 22" Jansport Boost backpack with three major compartments and two minor compartments for a 4 day on the Triumph 2/9/17, 7 day on the Glory 12/1/19, 5 day on the Valor 12/30/19, 5 day on the Valor 11/29/21, and a 4 day on the Valor 12/23/21. I took a 2 hour Greyhound to New Orleans and walked from Union Passenger Terminal(2/9/17), Canal at St Charles(12/1/19, 12/30/19), and St Charles at Poydras(11/29/21, 12/23/21).
On the 7 day cruise, with the aid of a compression packing cube and rolling my clothes, I was able to fit in the main compartment: 7 2X t-shirts, 1 pair of size 14 jeans, 1 pair of 2X yoga pants, 1 3-piece swimsuit(pants, zipper vest with built in support bra, and mesh back undershirt), 1 2X dressy top, 1 2X coordinating dressy cardigan, 1 pair of black jeans(?), socks, bras, and underwear, in addition to what I was wearing. I only brought the ASICS sneakers I was wearing.
I was wearing a jacket with inside pockets. I had my passport, S8, boarding pass, cash for onboard and in port, and metal card wallet in those pockets.
In the outer compartment, I had a cord organizer with all of the cords and wall plugs needed for my electronics, S7, portable battery charger(10,000 mAh), pen, mechanical pencil, lead, and extra hair elastics. I had a Quirky extension cord in the bottom compartment. I had a portable battery brick(26,800 mAh) and an iPad 2 in the main compartment.
In the middle compartment, I had two paddle hairbrushes, a comb, two aerosol cans of Veet shaving cream, solid deodorant stick, and a 1 quart heavy plastic bag with an actual zipper(not Ziploc) with travel size toiletries with space left over. There was also a gallon size bag with a pill organizer, one pill bottle, extra contacts, contacts case, travel size contact solution, small bottle of Aleve, and small bottle of fexofenadine in that compartment.