[2.2] COC Barrage wand occultist

We're using high base crit wand with barrage to proc arctic breath and ice spear.
Why not using quill rain? You could, I just prefer / want to try with wand in this build, also quill rain has 5% crit chance while wand can go up to >9% base.
Why witch / occultist? Actually you could go Assassin / Deadeye / scion with this build and acquire better result than me, I just like the extra power charge and extra curse on occultist

https://www.pathofexile.com/passive-skill-tree/AAAABAMBAABeBAcFLQVCCC4NjQ3RD6sWvxmKGY4aSBvIIG4i9CP2JIsk_SaVKgstHy5TMHw2PTfUQZZCekMxSn1Ms0z_TZJOKlAwUEJRR1M1VK5VS1XGW69fsGHiY0NlTWpDaxdsC2yMbWxvnnBSdO11y3cHenB88H11fdKD24TFhxOHdonTjAuMNo19jX6Nv5EHkyeVIJcGm7WcpJ2qoS-jiq6zuXy747zqvTa-ir6nwFTDOsSiykrNmM_d0B_Q9dNv037UI9rB217fiuOE45_nVOpi7LDtP-2D7g7veu_r8Yr0KPzF_rr_3g==
For the remaining points I will probably grab more life in Hired Killer cluster and / or projectile damage near ranger start area. Grabbing remaining frenzy charges also good option to increase attack speed and damage.

Bandit: Life, Attack Speed or Passive, Power Charge
Ascendancy: Forbidden Power for powercharge > Profane Bloom > Malediction for +1 Curse

Wand: Rare with high crit, preferably >10%, high attack speed >1.45, increased spell damage, crit chance for spell, cold damage, projectile speed, global crit multi.
Shield: Rare with evasion, life, resist
Helmet: Rare with evasion, life, resist, whatever stats missing (alternative: Rat's Nest, Starkonja's Head)
Gloves: Facebreaker for crit multi (alternative: Maligaro's or Rare with evasion, life)
Boots: Rare with life, evasion, resist, movement speed (alternative: Atziri's Step)
Body: Rare with high evasion, high life, resist (alternative: Belly)
Belt: whatever stats are missing, life, resist
Amulet: whatever stats / resist are missing, crit chance, crit multi, accuracy
Rings: preferably diamond based, accuracy, life
Jewel: %Life, cold damage, attack speed, projectile damage, spell damage, crit chance, crit multi etc.

Gem link:
Head: Vaal Haste - Vaal Grace - Frost Wall / Blood Rage / Faster Casting - Increase Duration
Weapon: Lightning Warp - Faster Casting / Rapid Decay - Less Duration
Shield: Blasphemy - Warlord's Mark - Ice Golem
Gloves: HoI - HoT - Curse on Hit - Assassin's Mark
Boots: CWDT - Immortal Call - Arctic Breath - GMP
Body: Barrage - COC - Arctic Breath - Ice Spear - GMP, for 6 link can put life leech, crit strikes or crit multi

Jewel

Basic stats

(with 3 endurance charges)

(with 7 power charges, 3 frenzy charges, blood rage and ice golem)
Barrage:
Ice Spear:
Arctic Breath: