We stayed on the Lido deck on the Diamond (Sapphire's sister). It's a fantastic location! It was so easy to pop out to the pool or buffet restaurant.
The balcony will be totally private, so no worries there, and it is smaller than ones on Caribe and Dolphin.
We had an inside cabin, so that's all teh info I can offer.
We LOVED the Diamond ... loved all the choices for restaurants with Anytime Dining. That's why we are going back Oct 30th.
Regarding the wedding, check the princess web site -- I bet they have some info.