Don't get a forward room. Forward has the most movement. I am prone to sea sickness, and my worst case was when I was in a forward room. Get as close to the middle as possible, it doesn't have to be lower, just closer to the middle.
Ok, I looked and I would either have to do Deck 2 which I have heard is not good for motion sickness or switch to a Cat. 11. So is a Cat. 10 much better than an 11 or should I just switch and get a midlle, middle inside room?