If I have to wait to purchase a back, there is a greater chance the top will become a UFO. I guess I'm always thinking one step ahead of what I'm doing so the enthusiasm for the finished product continues until it's actually done. I've been quilting long enough that I'm comfortable with the craft but I still do not put a pieced back on mine. My luck is that it would shift in the quilting and end up not being up to "my standard". The only piecing is to make the back bigger, not designed. I love the colors you put together in your quilt. As you said, very restful--and they compliment each other. As beginners, we tend to select a pattern we like, not necessarily because they are simple. Just jump in and you've done quite well.