We did Christmas 2014 for the first time, although we had previously visited at spring break including Easter Christmas was far more crowded but we had a great time and you will too going in with the right attitude and expectations. The fact that you are there a long time will also help, since you can spread things out and while we left on December 30 I have read that crowds decrease a lot after New Year's. We did plan a park break for Christmas Day figuring if we were skipping a day anyhow that would be a good one to choose. We were worried about the parks closing due to capacity but never experienced this. As others have noted rope drop will help a lot, although our kids are older and weren't interested in being up early every day so sometimes we planned to arrive late afternoon and for those days we used our FP and planned to go to larger capacity attractions. I spent a lot of time obsessing over touring plans to try to maximize things but didn't really follow them, it was too much planning and stress. While we may not have experienced as many attractions as on other trips, there were so many other opportunities that are not available other times of year--all of the decorations, the Christmas traditions in the countries in Epcot, the lights in DHS (we actually spent a long time one evening having drinks and just enjoying the lights and music) and there was even a special holiday comedy show at DHS, and the holiday twists on evening shows like Illuminations. We also planned meals in resorts we had not visited before to see their decorations--they all have their own twist and this also helped us seek out new restaurants. With reservations we never had a long wait. If your tastes and budget permit consider doing something like the Fantasmic or Rivers of Light dining package, you are guaranteed great seats with a much shorter wait and you won't have to queue up 1+hour early just to try to get any seat. We haven't done Candlelight Processional but I am sure that the same is true. With advance planning, an openness to experiencing the special things that the holidays offer and the generally high spirits of the CMs and tourists even if you might not ride every single attraction or won't repeat on your favorites, and going in understanding that it will be crowded but that you aren't going to let it get to you are the keys and you will have a blast.