I'm a firm believer in organizing and storing things by how I would normally look for them when I want to use them. It works for everything...file folders, books, kitchen utensils, clothes, fabric, everything.
I look for fabric by color, it's that simple, so that's how I store it. I have no seasonal, holiday, novelty, juvenile, themed, large scale, flannel, or fleece fabrics...pretty much nothing but blenders, solids, small scale prints, and batiks. All my fabrics read as single colors, so organizing and storage is very easy for me, as is finding exactly what I want in the least amount of time. It's worked perfectly for me for many, many years without any major overhaul...just lots of additions.