My sister made a quilt out of sari fabric. She isn't the best seamstress and the blocks came out wonky. If all of the fabric can be washed and can stand up to the heat of an iron, I would probably back all of it with SF-101. It is a fusible interfacing that to me looks like cheap cotton fabric. I purchased a whole bolt with a good coupon at JoAnns some time ago. A lot of the sari fabric seems to stretch some. I too am not sure about using the fabrics with sequins in a quilt that will be used. Save those for a wall hanging. It will be a beautiful quilt. I can't wait to see it.