Have been on this ship twice, once to Mexican Riviera, a port side mini, aft.....D722, and then, to Alaska, in a Starboard side balcony cabin, C302 on Caribe Deck. The last cabin was near the forward elevators, and the first cabin was behind the aft elevators. We felt more vibration in the aft cabin, but it was kind of neat..........like the old "magic fingers" deal you could pay for in motels. The only time we felt any motion was on the way back to L.A., from Cabo, and that was because we were going faster than we did on the way down, and against the flow.
I use the patch, my companion on each trip did not use anything. On Mexico trip, husband was not bothered by motion, and on Alaska trip, Mother was noticing it, but not bothered by it for part of one day. If you know you become motion sick, do try whatever helps you........Meclazine, the generic form of Bonine is a lot less expensive, bought from the pharmacist, but not prescription. Patches require a prescription. Many people use sea bands which are elastic bands for your wrist, and can be bought on board. Some people swear by ginger tablets. You have to just "be prepared"...............you probably wont even notice any motion. If you do have a problem on board, you can go to the doctor on board.........it would be expensive, but worth it for the peace of mind.
Buy some meclizine or dramamine, if you know you can tolerate it, take one the morning before you board, and see how you do...............
Have a wonderful cruise! The Star is a great ship..........