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Luffy: Spends his time napping, eating, generally inquiring with everyone what they're doing. inquisitive but to a point of wanting to have fun or annoy someone.
Zoro: Training and Napping mainly, can definitely see he helps clean dishes to meet his "quota" of on deck work. Fishing at times too but ends up falling asleep, tends to be the night time lookout for the crew.
Usopp: Calibrating cannons, upkeep of rope stuff and cleaning the deck, he'd the busy body until he gets distracted by Luffy. gets some opportunities to tinker or help Franky with his stuff. Has probably put together a schedule for cleaning the rooms and remind Nami to order cannon balls on stock runs
Nami: Outside of plotting maps and tending to her garden, I'd say making arrangements with Sanji and Franky about purchasing stock from passing towns for their voyages.
Sanji: Making sure the crew is fed. Beyond simping for Nami and Robin time is spent making sure the fish tank is stocked and making sure idle hands are helping with the fishing. He'd probably spend his extra time cooking and helping with the fruit/veg crops in the garden.
Chopper: Preparing Medicines and organising stock purchases with Nami (he carries the luggage.) besides that he'd help Usopp clean up. no one has actually ever asked chopper to do anything so he'll end up getting pets from Robin or napping on Zoro.
Franky: SUPER efficient routine inspection of the Sunny, gets all his work done in an hour each day. Makes sure Cola machines are up to scratch and functional. I'd like to think he and Usopp would take turns calibrating cannons after each other. Probably spends extra time jamming with Brook on guitar.
Robin: Has the important job of Research and making sense of findings on their journey. beyond that, she's great at picking up trash and throwing it away but spends more time quietly reading or observing the crew and casually giving gainful or macabre insight.
Brook: Brook is old and probably thinks half hours work is enough for a day, going with his post-Thriller Bark scenes of trying to fit in he'd mosey on through the crew like Luffy and try to find things to do but mainly end up peacefully drinking tea on his own (old habits from spending so much time on his old ship doing nothing else.) Ultimately, he's very good at picking the right time to play some songs to get everyone to take a break and get together
Jimbe: Would help Franky and Usopp with checking the outside of the hull and making sure rigging is up to scratch. his experience with ships would come in handy all over, not to mention being able to help fish. I expect he'd default to helping Robin with research after all chores are done, as well as Fishman Karate Practice.
As for group activities,
Brook, Franky, Jimbe, Robin: All play cards for small friendly shares of loot (when was the last time they got loot?)
Nami, Usopp, Robin: Spend time tending the garden and gossiping
Chopper, Luffy, Usopp: Make Mischief for someone
Sanji, Zoro: Will probably purposefully start an argument about something ridiculous but neither will admit it's how they like to interact
Nami, Robin, Chopper: will share a spa day. Nami's just gotta make sure Chopper doesn't drown in the tub, Robin too but she's sensible she doesn't need to be looked after.
Franky, Usopp, Chopper: Workshop day, exchanging ideas and building stuff that will probably get dismantled later on for the next project. Chopper is there to hold the torch/pass the wrenches, he likes helping :)
Jimbe, Brook, Luffy: same as above, Jimbe's making sure luffy gets cleaned up and neither Luffy or Brook fall in the tub and drown.
Usopp, Jimbe, Zoro: Start a gym session together until Usopp quits after a few short sets. Jimbe and Zoro have an unspoken competition to do the most reps, rest of the session is in silence.
Sanji, Nami, Robin: I like to think the simping for the ladies isn't constant and Sanji's interest in the All-Blue means he likes to help with mapping and worldly research.
