Youngcouple, wecome to LCT! I think you will probably find other young couples honeymooning right along with you! Also many "young at heart" couples in their 40's and 50's, either honeymooning for a second marriage, or enjoying a special anniversary. We saw both when there several years ago to celebrate my son's college graduation with his girlfriend and my daughter.
Back then, you could not book excursions online, and I got temporarily shut out of some excursions we wanted at first, but they all came through in the end because of cancelations. I would take the advantage you have of booking on-line and go with this, just to avoid a problem. You can do searches on this and other boards to see discussions of what you think you would enjoy.
My favorite place for dinner was L'Etoile, no reservations required. We only booked in Apicus one night, and did that after getting on the ship.