I think I misunderstood your original post. Trying to clarify - I thought you were feeling overwhelmed because you're spending all your time on washing/sorting the donated fabrics, but after your second post, I'm thinking you're feeling overwhelmed because there's so much fabric and not enough time and/or people to sew them into tops?
I have a friend who also makes a LOT of quilts for charity - Linus, homeless vets, passage quilts, etc. She raised funds and invested in an Accuquilt Go! cutter. She (or a helper) will cut "kits" from the donated fabric. The kits are passed out to anyone who likes to sew, and the finished tops come back to her, and she'll either have someone tie them, or she will quilt them. This might be a great option for you, especially if you have lots of volunteers who would like to sew the tops.