I haven't used it myself, but a class instructor passed around a lap quilt to show us what silk batting felt like. Wonderful! It was her favorite batting for hand quilting because it is very easy to hand quilt. Other threads have noted that silk batting is even warmer than wool.
If you can afford it, silk batting is the most luxurious, warmest, and easiest to hand quilt. (I don't know about machine quilting silk, but assume it would be fine.) I believe quilting lines need to be fairly close together (2 inches?).
Quilter's Dream wool or Hobbs wool batting would be the second choice -- very easy to quilt by either hand or machine, not quite as warm as silk and heavier than silk, but still extremely nice. Quilting lines can be a little farther apart with these (4 inches?).