you're build looks solid, but imo you're over slotted for survivability.
ST rotation would just be Bitter Ice Blast - Freeze Ray - Ice blast - repeat.
when its a full mob open with Blizzard - Ice storm (about halfway through blizzard animation) - ST rotation
i got you more DMG, better end management and more rech.
if you get into trouble you still have your heal and PFF.
Defender (Force Field - Ice Blast).mbd