Carnival is a younger group of cruisers. I have cruised Carnival Spirit and Pride out of SoCal because it is convient for me to drive over to San Diege and leave my car with my son. The one thing that sets these two ships apart from other ships, they are the same class, is the Gym and especially the Steam and Sanna facilitied. They are fantastic. I never use the shower in the cabin. I go up to the mens locker room in the late afternoon for a steam, shower and shave. Did I forget to mention that I am a dirty old man?
I also send an email to the Mater ter de,(bad spelling), to request a table of other single travelers. I have made some great friend on these ships. They have FOD meetings on a daily basis on all five of my Carnival Cruises.
The only problem that I might forsee with your Dec. 14th trip would be "Rug Rats or Curtain Climbers". Kids might be out of school this time of year and Carnival does cater to families.
Hope this information is some help.