I have the '13 CVO Anniversary. My girlfriend has no issues with the passenger pillion but she is used to riding on the back of my '05 CVO Fatboy so anything is more comfortable than that. I have been looking at custom seats and I am leaning toward Alligator Bob in Illinois. Many of the seat manufacturers will use your old pan but since Harley uses a plastic pan, the "good" seat manufacturers will require a metal pan for durability and to maintain shape. I suggest if you are only going to replace the passenger pillion then call around to Lepara, Danny Gray, Saddleman, BMS, etc. I'm sure you can get one that will match pretty well and get her the comfort she needs.
When my woman is happy, the whole world is happy. When my woman is unhappy, I leave town.