My bet is it will be fine and fluff up a little when you wash it. The first quilt I ever made was with Mountain Mist Blue Ribbon cotton batting, which is a very antique "flat" batting. When I was half done, I took it in to a quilt shop to ask about the flatness and was told it was fine. At that time I thought a hand quilted quilt was supposed to be more puffy, like a modern day comforter. That quilt has been much used and loved for maybe 20 years now (it was a baby quilt).