Superior Bottom Line is perfect or your bobbin: use it for regular piecing and when using decorative threads and stitches. It is a smaller thread, so it lets your decorative threads really pop!
Perfect for all of your piecing because it is 100% polyester and very fine but strong. It’s 60 wt, so takes up little space in your seam allowance so it helps keep your scant quarter inch from overflowing into a fat quarter inch!
I use this most all of the time!