Here's my WD on T6 Ghom. I kill in about 10 seconds. This video is me killing Ghom and then showing my gear and skills afterward. I figured it'd be a nice break to see it in action. <shrugs>
http://www.xiaix.com/video/WDT6/
your killing to slow imo for a WD, you dont need 3x zuni for ghom, u are better of with 2x blackthrone on pants and feet, belt the witching hour for chest tyraels might, you can also change your build
Witch Doctor - Game Guide - Diablo III
with this i kill him in 4-5 sec just a tip ^^