I actually do both, but I only buy fabric that I really like and to be used for a specific project. Also my stash is not as large as your description. I used to buy what I liked when I saw it with no project in mind and I find that, that fabric is hard to use. I enjoy seeing all the fabric collections but shy away from buying. These collections do give inspiration for pulling together fabric collections from your own stash, which I enjoy doing. I am in the process of making my own kits with fabric and patterns together in a bag. This helps me remember what project the fabric was intended for. Like many others I will not be able to finish all the quilts I have planned in my lifetime.