One of my new favorite builds is a Priest !
But I never played a PURE Priest (or whatever pure class) !
But a Priest with Rangerskills and 1 or 2 Warrior skills and/or Mage skills too.
The most fun for me is using skills as Charm, Blind, Fear or Curse, Summon Ghost, Demon and/or Undead ... & using my Creature . And the combination of skills can be handy and really fun :
Hide in Shadows & running to that enemie I want Blind or Charm. Or use Thousand Strikes and if that enemy try to run away, I use Stun Arrows first ... So many nice combinations are possible, it's fun & great to discover your own favorite skill combinations
For playing as Ranger (still with my Priest build), while my allies do the most durty work for me, I use Stun Arrows mostly and in Flames of Vengeance part, I try sklills I never used before like "Way of the Ranger", it's cool !
Mage skills I used most : Firewall & Healing & sometimes Magic Missile (skillp. via gear)
Warrior skills : first Rush Attack, later on Thousand Strikes and sometimes wearing a piece of yewellery with a warrior (or mage or priest or ranger) skill on it
I always love it to find/buy as much nice yewellery with a skill on as possible so I can in one playthrough COMBINE skills so I can in fact CHANGE my current skill-build a little bit (or more than a little bit!) and I find that really Fun & Fantastic to play that way !!