This is a hard question as every quilter is different.
Some want the latest /newest lines and don't mind paying the going rate for fabric. Others (like myself) don't care how long the fabric has been out. If you have a source for older lines of fabric that you can offer at a good price, along with some of the new stuff you may attract both crowds. I tend shop online mainly because of the price but also because I find that a large quilt shop with all the bells and whistle totally overwhelm me with the choices. Just my opinion.