I’m leveling a PB Witch Hunter vita/chaos and I think it is OK for the moment.
I just reached Ultimate but Elite was quite easy.
I’m lvl 72 and already have more than 1000% in chaos/vita damage.
It is almost impossible to find good stuff to increase PB, HS or NE though.
It will probably be a problem later.
At lvl 65 I equipped a Blood orb of Ch’thon and it increased the damage of my PB by at least 30% since the Cold part is more or less the same % as Vita or Chaos parts.
It is better now but I had hard time with mana management during a while.
I crafted a Terror relic at lvl 35 and it helped me a lot to progress.
I’m not so squishy thanks to all the life leech I have.
This is the build I’m doing, few points may change at lvl 85 following my leveling in Ultimate.
http://grimcalc.com/build/430dxv
The points in PB are only here to increase the number of projectiles.