Couple of things that we found really helpful:
this beach blanket while in port: https://www.amazon.com/gp/product/B07CXL453D/ref=ppx_yo_dt_b_asin_title_o05_s01?ie=UTF8&psc=1 It is super lightweight, almost like a parachute, came with stakes and it was huge for the 5 of us! I am excited to use it in other ways too. I got it for $17 on deal.
These metal hooks were awesome for holding my lanyard, drying my suit, etc: I picked these up for $6 https://www.amazon.com/gp/product/B0787Q54M1/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1 We had 2 cabins and 6 per cabin was great!
Also we did bring towel clips, a small travel speaker, and a deck of cards- used all of those!
We designated one empty suitcase for dirty laundry at the getgo so that kept our cabin organized.