It's your quilt - do whatever you want!!!
I made 4 summer quilts, one for every bed in my house. Each one is a top and a back, no batting. They are the perfect weight for sweltering NJ summers. Some may call this a "coverlet" not a quilt. Whatever. They look great on the beds and they are used all summer. That's all I care about, not the name.
I also have made quilts with yardage of double knit fabric as the batting. I love the way it drapes and I think it's actually warmer than regular batting. I don't care that it's not puffy. Again, this is my quilt, for my use (or for me to gift) and that's what I wanted to do.
So do what you want to do. I think it's a great idea!!