Or talk to the Cruise Director and see if there's someway they can work the proposal into one of their shows. Maybe even during the ice show or in the main show lounge. They'll even schedule the photographer to be there to record the event. They love doing stuff like this as it involves the passengers and makes their cruise more memorable - not to mention it'll be something neither of you will ever forget.
Your agent can get in touch with the people on the ship so you can begin the planning ahead of time.
Sounds very exciting and romantic!
Travel Agent/Cruise Specialist w/12 yrs exp and 47 Cruises on 11 cruise lines! Favorites: Paul Gauguin - Tahiti: Uniworld River Cruises - Europe; Celebrity Solstice-class ships; Holland America - 12-nights Baltics & Russia; RCCL - 14-nights Greek Isles, Turkey, & Croatia; Holland America - 14-day Alaskan cruisetour; 10-night Canada/New England cruise; 21 days Hawaii w/7-night NCL cruise; Oceania - 25 days in Asia; more than 3 months touring Europe by train. And many all-inclusive resorts!