Your first build is the skill set that seems to be what most people are using, with respect to everything except Rain of Vengeance. Im not sure if this skill has recently been reconsidered to be great or something, but I dont think its very useful for its cooldown. All of the runes except one require the user to be generally stationary for the enemies to take the damage of the spell, which is really contradictory to solo-DH, which is 90% kiting.
Your second build is pretty much the same, but with vault instead, probably the better of the two if thats all you feel like using. Personally I dont see the appeal in that vault rune, I think if any Tumble or the one that stuns is better.
Im only in A2 inferno, but I've been using that first build that you have, except I use the Hooked Spines rune for Caltrops, and instead of Rain of Vengeance, I use Shadow Power with Blood Moon.
I prefer Hooked Spines on Caltrops to Torturous Ground, after using both extensively and finding that most of the time if an enemy runs onto the caltrop after the caltrop has immobilized other enemies, they wont be immobilized, only slowed the 60%. Hooked Spines on the other hand, slow everything 80% regardless of when the trap is activated by various enemies.
Shadow Power's value is in the survivability it offers; if you're at a dangerous amount of HP, you can hit SS and Shadow Power and just keep firing into a crowd with Nether Tentacles, and generate likely all your HP without using a pot. I'm pretty sure that also leaves you with enough discipline to SS again after lifestealing, to escape the area if everything isnt dead.
Edited by FlyMolo#1223 on 5/26/2012 6:26 AM PDT