New fabric is sorted by project. Unused fabric is sorted by color except specific holiday fabrics (those are kept together). Scraps are also sorted by color except specific holiday fabrics (those are kept together).
Just a thought -- too much thinking/planning with a scrappy quilt is not a good thing (you will drive yourself crazy -- no pun intended). I just pull a fabric out of the container, the only exception for me is placing the same fabric too close together.