I am booked on the Conquest and I know no one will know this first hand because she is a new ship, but maybe you can tell me about other mega ships. Just how private is the balcony? Is there any way I can tell before hand if the upper decks will have a view of my balcony?
When I was a little boy my mother would give tell me "Don't do anything when you're by yourself that you wouldn't do when I am here" as a guideline for behavior. Of course I didn't pay attention to that and got away with all kinds of things all the time.
Now file that away in the back of your head
Many years have passed now
Now I am on a cruise ship, standing on my "private" balcony. I lean over the rail and watch as the ocean goes by. Glancing to my left, my right, up and down I see others doing the same. So much for "private". I hate to spoil whatever plans/fantasies you may have for your balcony so I will offer just one piece of advice. Wait until dark. Mom will be asleep then.