Congrats on getting married.
I took the reposition Voyager cruise in November 2005 and it was cold with a bit of snow flying when we left. By the time we woke up the following morning, we could at least enjoy some outdoor activities like golf and the hot tubs.
I have seen the 12 night itinerary and would jump at the chance to go on the particular cruise. Enjoy the colder weather, sleep in a bit, and relax.