in 4s meta though, the niche isnt as strong now that WD may not be exactly the top choice for 1 of the dps slots (there are some alternatives especially both channel meteor wizards) as not every class gets the same benefit as WD from a few globes. zwiz and zdh are then weighing more damage vs ignore pain and movespeed, essentially.
barb can be replaced with wiz and dh supports, both of which sacrifice a few globes, optional movementspeed buffs, and ignore pain in order to provide nearly equal toughness buffs and much larger damage buffs to group.
zdh also plays the role of tagging monsters very easily without even needing to leave group as the build runs marauders 4set bonus so you can place a sentry and shoot MS windchill offscreen. wiz offers grouping skills too. both can be made quite mobile.
to put it into perspective, at around 1200 paragon in season 11, my friends and I ran gr 111 for #897 4man clear with znec/zdh/2rathma where we barely had a 108 with zbarb instead of zdh. on the other hand, frozen elites gave us more trouble but all was well as we consistently cleared 109s.
for those who play 2man and 3man, zwiz and zdh prime choices for supports there. zdh + RGK necro was a top 2man comp in season 11, and both of these support classes fit into 1 dpser 3man comps quite well.