I would pick a Longwool breed like Leicester Longwool or Wensleydale to spin for needlepoint yarns. Wensleydale makes beautiful needlepoint yarn, high luster, so when dyed it really glows. I'd use worsted-style spinning, fairly thin and smoothing it down so it won't be hairy -- I'd probably go so far as to ply from the start of the bobbin to ensure I kept laying the fibers down in the same direction, to minimize hairiness as much as was possible.
(posted by me this day on TechSpin)
