Kim, this is just my opinion but if you are not taking one of the larger E's (like 603) I would go for cabin # 633 as it's in the middle of the ship and closest to the waterline which makes for the smoothest ride. Also, you have no neighbor on one side of you! If that one was already reserved, I would aim for 728 or 733 on the next deck up for the same reasons.
728 looks particulary good as you are down the hall a bit.
