I would forget about most melee oriented builds as the chaos sanc is pretty hard to do unless you are using a berserker barb or something like that. Summoner necro is probably the easiest, although it can take some time to get through certain areas. Bow and Jav based amazons require some pretty specific gear to be able to survive in hell on their own. Wind based druids can be fun, after about level 18 or so and can survive in hell, but without some good gear this will be pretty hard. Death sentry + dragon claw kicker assassin is a pretty solid build that can do well even without good gear. Dual-elemental sorc is pretty effective, even with weak gear. Try a fireball/blizzard or metor/frozen orb centered sorc and you should be fine.