I have to agree with EnglishBob that if you use ERC, you could easily have 50-100 parts, otherwise I would likely keep is below 20. The idea of some independently posable bangs or hair tendrils would do a lot for realism. I've always thought it would be cool to have morphs or the ability to go from neat to mussy. Good luck on your project. i am aleays impresed by good hair.