My stash NOW is obscene. After almost 500 quilts, I have a very good sense of what I am likely to want. IMHO, you can't go wrong with "reads as solid" in colors you like. I also have a large collection of 'naturals' (like scenery) and 'kid prints' for the foster kid quilts I make. I have a smaller collection of stunning oriental prints, usually with a specific quilt in my head. A fine quilter I've loved for years says that is you generally make smaller projects, get a yard or even a fat quarter. If you mainly make really big things, get 3-4. I have found that everything I buy gets used.