Figured I would share my build here as it seems ridiculously OP to me. It revolves around sharpshooter, High stacked +crit damage, and cluster arrow. I have used this to solo all of act 1 and some of act 2 very very easily. It uses rain of vengeance to stun lock elites/bosses and you blow the shit out of them with cluster.
-The second option is using cluster with shooting stars and rocketeer passive. This option is good for bosses with adds or elite packs because initial hit kills adds and the rockets will typically hit boss or finish the adds off.
Can switch generator/companion around still. But Ballistic is almost a must.
Note this build works best with 2h crossbow, and rings/amulet/gloves with +crit damage.
Before you say "herp derp crit is unreliable." From my experience in inferno you have to kill the mobs really fast or you die and this crit build does a great job of bursting. Yes you could keep steady aim and have 20% more damage over sharpshooter with more sustained damage but the burst from the crit seems more effective to me.
Open to suggestions!