Intentionally, VSS is suppose to be an easier way to apply texturing to any object that contain material zones with identical or similar settings.  It is a one-time application that changes all zones at once.  BB's initial release contains template zones specific for texturing human (or non-human) figures.  But it can easily be adapted for other use.  Creating a template for hair is easy, however you need to settle on a grouping of shader nodes which will optimize hair appearance.  Olivier at RDNA posted some time ago an arrangement of shader nodes to enhance hair realism in Apollo Maximus.  That is easily adaptable to VSS except you may need to create an additional displacement map to accomplish the full effect.  Keep in mind, depending on which hair style you use from any particular vendor, you may need to modify the Rules zone to comply with material naming convention.

Under P8, there would be no need to include AO in the hair material, it's lighting system has been greatly improved since P7.  IDL would take care of the fine detail.  Increased render time will most likely appear with the presence of displacement mapping and transmapping, which would not be practical for animation.  I could post Olivier's shader arrangement, if you are still interested.