One thing to remember, when hand quilting is that you don't see the thread like you do with machine quilting. When machine quilting the is a line of thread on top of the fabric. With hand quilting, the thread is mostly between the layers with a little stitch of thread peeping through. Color does not make a difference with hand quilting like it does with machine quilting. I prefer not to use variegated thread because the thread doesn't show enough and I find it looks very disconnected and some of the stitches almost disappear because they blend into the fabric and others really pop. I like using a neutral color that is just enough different that I can see the stitches. Recently I used navy thread to quilt a navy print fabric and I could barely see what I was doing some of the time. Don't give up...hand quilting goes better the longer you do it!