Not related to a GTY booking, but we did do a BTB sailing once where we had to change cabins. On turn around day, the cabin stewards do essentially everything for you. The take anything hanging in closets and carry to new room, drawers do not need to be emptied since they merely switched drawers. The did ask us to pack our bathroom items into either a carry on for transport to the new room. But this was pre Covid, so things may have changed. It is worth it to ask.
LOL, we thought we would help the cabin attendants since they are so busy on turn around day, but they said they were not permitted to let us help. We don't know if that is still the procedure.
As far as the Insides go, on Regatta the only cabins that may have motion for you are 7002, 7003, 6010, 6011. We had 7002 on Insignia for a sailing from Sydney to Papeete with quite a bit of wind. Motion typically does not bother us at all, but if I wanted to read or use my ipad/iphone, I needed to go down to Deck 4 since staying in 7002 doing those activities made me a bit queasy. No problems ever in any other Insides on Deck 7. If we book Inside we book Deck 7 since it is close to laundry. We have been right next to laundry and have not been bothered by noise or traffic. We are usually up before laundry opens in the morning and at night the laundry closes at 10 PM.
Enjoy your cruise!