What is your pattern that you are going to use hand quilting? Or are you hand quilting and hand piecing as well?
Hand quilting: I tend to get a thread color that will stand out on the backing of the quilt. If this is your first time hand quilting and your stitches are a various size then I would get a blending thread color.
Hand Piecing: I use thread that kinda goes with the fabrics. It blends in when the seams are finger pressed especially if your stitches are slightly farther apart than on a machine. I get 15 + to an inch and sometimes that is too far apart to hide the thread.
I do both piecing and quilting by hand.