When choosing wool for sculptural needle felting, consider the benefits of using batting rather than roving.
No matter what the breed of sheep, wool that has been prepared into batting seems so much easier to needle felt than wool that has been prepared into roving, tops or sliver.
The main difference is that batting is messy! The fibers are unorganized and as you tangle them together with the felting needles, they shrink together from all directions.
With roving (aka tops or sliver) the fibers have been combed so they all run in the same direction. As you tangle the fibers together with your felting needle, the fibers shrink along the lines of the fibers leaving grooves or stripes.
Wool prepared into batting for is loftier than roving - it holds more air. And to make needle felted characters that flex and move, this quality is important.