I just wanted to share a couple thoughts regarding the FE experience we had in case it may be helpful...
On our cruise last Christmas, the person who managed the FE list used google documents to keep the list current. Since the content was updated real-time whenever she made changes, when we clicked the original link she sent us it always displayed the most current information. She was able to add cabin numbers as people in gty status got their assignments so when we all left home we had cabin numbers for everyone. The exception was for some of us who were upgraded after we left for the cruise (we were one of those folks!), though if you had a laptop you could always check the list even in your hotel room the night before the cruise.
For those who chose to upgrade at the port we had another way to address that. We had a DIS meet the first day of the cruise and we updated any changes at that time. We had a small group so it was really done informally, but if the group is large, maybe Guest Services would make copies for everyone. Another idea our group had was to post the most current FE list outside the organizer's cabin door on the first day. Then we would make sure we took our list down to her cabin to update ours. You could just use DIS names so there really isn't any personal info for all the world to see.
There is one more reason that it may be helpful for people to have current FE lists that detail the cabin number and family. Some people chose gifts specifically based on age and gender, so for them it would not have worked to just put the gift in a cabin with an FE, they would need to know specific cabin numbers for each family.
Oh, just wanted to add that if you decide to do 2 FE groups due to size, maybe there could be 2 FE organizers that are assigned certain DISsers...then you can use the same strategy above, but it would be done with 2 groups vs. 1. Not saying you should do 2 groups, but I think it could still work if you did. Last Christmas we had about 20 in our group and it was a good size. It took my DD's and I about 45 minutes to distribute FE gifts, though we wouldn't have minded more either!
One last thing (sorry, don't mean to be butting in, but I learned alot on my last FE exchange and wanted to help w/ideas if you like them)...we made a rule last year that you could distribute your FE gifts whenever it was convenient for you and your family (so as not to interrupt something you really wanted to do onboard or in port), but we did say not to distribute gifts the first night or the last night...first night b/c not everyone will be totally unpacked and have their FE's up and last night b/c everyone will be packing.
Okay, I am done now

Again, I hope y'all don't see me as butting in...just trying to help if I can!