This build is aimed at pushing solo with the Shadow's Mantle set and the new reworked Holy Point Shot (Impale now throws two additional knives). It has a very distinct new playstyle and is very consistent with little fishing involved, and can push into the high 90s with endgame setups, so it is roughly 2-3 tiers behind the current top DH builds.
There's not a lot of room for variation here. Full Shadow's set, Karlei's Point, Holy Point, Chain of Shadows, Endless Walk are required, equip Convention or Elusive Ring and cube the other ring, preferably equip Strongarm Bracers, as they are the only really useful pair you can get for that slot. With Gogok up you will need CDR on one item (preferably shoulders). Supplement that with attack speed on gloves and perhaps rings, stack elemental damage + chc + chd where possible. Try to get Impale damage on boots, helm and quiver.
D3planner setup with optimal item rolls: http://www.d3planner.com/345268342
This is an elite hunter build, just try to vault through the rift until you find a pack, then focus on it at all costs. Killing trash without elites around will almost always be worse than just looking for the next pack, so try to stand on top of your main target to make sure you hit it with all three knives, and let the area damage kill some trash. Make sure you keep up your Elusive Ring with Vault or Shadow Power and try to time your vaults a little to apply the Strongarm buff right before your lightning CoE. Generally, you are pretty tanky and can fight almost any elite, but don't hesitate to just skip a very terrible pack that would take too long to kill.
It's possible to play Focus + Restraint setups and / or Lord Greenstone setups as well, but they will very likely be a couple tiers worse. The only big variation here would be changing Awareness to Leech once you have grown comfortable with the playstyle, that will let you play a little bit more aggressively because you have better sustain. For a little bit more damage, you can equip a Unity instead of Elusive ring.
Feel free to watch the video for more in-depth explanations and the reasoning behind some of the item / skill choices etc.