One thing that improves them is to use an anisotropic shader in the alternate specular slot, used either on the cornea (if the character has such a material) or on all of the eye-parts (eye white, Iris and Pupil) It really makes the eyes look more wet and real.

FREEBIES! | My Gallery | My Store | My FB | Tumblr |
You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.