A thin batting. Seems like a silk backing makes sense. Where do you live?? Can I come play?? 7 x 7 would give you a quilt 70 x 70.

I like the blocks "unadorned" - the fabrics are so rich all by themselves -

You could add a brown-tone sashing and corner stones to break it up. I think it's very nice. The larger pieces will give you great opportunity for quilting.

I agree with Mea12 ... as is, it's colors are simply elegant together. Also think your right to use up the embellishment & backing materials you already have if they are color safe, it will give you a great sense of satisfaction. A suggestion you might consider if you know how to crochet; you could crochet the border and/or sashing to make it slightly larger if needed and which would make it function more like a coverlet where the size wouldn't so much matter.

What would you think of putting minky on the back? I love minky backed quilts!