I would ask your daughter what she thinks she might like for her married bedroom as far as style and colors. You can use civil war fabrics for almost any pattern. Your daugher's response may lead you in a different direction than what you might be thinking in your mind. So I would most definately ask her. I would also ask her if she would like to help in the fabric selection.
Using classic patterns will always stay in style. The fabrics used in the quilt are what dates a project.
I would suggest looking at the books and patterns from Eleanor Burns. She has the process all described for you including the making different size quilts along with the supplies and the amount of fabric needed for each project.
Good luck with your quilt and keep us updated as you progress through your project with pictures if possible.
Pam M