We cruise at least twice a year and like to have a cabin on the Empress deck or Upper deck. Due to breathing problems I have problems with more than 2 flights of stairs at a time and use the elevator for anything more than this. If we stay any lower, I have to get to the muster drill early to avoid the stairs and don't want to be treated like an invalid at the drill.
We like midship because of the movement in the front and rear of the ship, but will take the rear if midship is not available. At least we are usually close to the dining room there. I also like to have a cabin that is about 4-6 cabins from an elavator or stairs and not right at that area due to noise.
I don't like an inside cabin at all due to claustraphobia. On a 4-5 day cruise, we book an ocean view and on a 7 day or longer, we book a balcony. We love the fresh air and privacy, and the views of all the ports from a balcony.