When I first started quilting, I thought I needed to use fabric from one line when I made a quilt. I think it was because I was a "color idiot" LOL! It took a long time, but I no longer feel the need to use one line, one manufacturer, or "better" fabrics all the time. I use what catches my eye, plain and simple. As long as it holds up to the prewash, I'll use it
All in all, I think my problem was color-coordinating. I found that using one of those "peepholes" for doors really helped me there. Looking at the fabric far away can really make the wrong fabrics stand out!