Dee has adopted the design of the sixities: Her clothing is African, her hair, her new name has been changed to Wangero Leewanika Kemanjo, and her hair is grown out. Her return home is for the purpose of taking some of the 'quaint' possessions to put on display. Her shallow motives for wanting these items are contrasted with the appreciation that Maggie and her mother have for tradition and the labors and personal artistry that the grandmother put into the quilt. Clearly, these items which are used as symbols represent the conflict of tradition and progress.
I would say that Dee's new clothing represents her break from the past. She is trying to be this new woman who has broken away from her mother's backwards life. The clothes symbolize that change. By contrast, I'd say that the quilts represent the opposite -- I think they represent her mother's way of life and her mother's values.