Something I've been enjoying a lot, particularly for bosses or harder mobbing when I want as much damage as possible, is quick reaction shifting for the 10 second bonus. I only really use reaction shifting for harder content or when I really just want to suck the fun out of party play. At level 20-30 this gives you 90 extra spell power and a whole lot of spell point reduction so I can freely use fully meta'd damage spells without stressing too much if I want to, otherwise I can just spam with impunity. Quicken makes this really smooth. I Poison Strike/Shot here is used because it's super fast, free, and you can cast immediately after. I don't bother hitting things with it as a pure caster.
While the one I use most does work with poison as primary, mid battle rotations or higher damage rotations are sub-optimal with poison primary since poison doesn't have yellow damage spells - one of a few reasons I use elemental primary instead.
I use the ice names below but it's effectively:
Cold Spike = Level 2 Yellow Single Target spell
Bitter Frost Burst = Level 3 Red AOE spell
Vein Freeze = Level 4 Yellow AOE spell
Situations listed below---
Prepping for battle/prepping before meeting up (This is what I use 90% of the time):
Stiffen Skin SLA > Poison Strike/Shot > Smoke Bomb SLA > Vial SLA just at the ground. Waste it, it's 1sp and you'll open with Obliterate or Multivial anyway.
(I have these right next to each other on a hotbar so I can easily press them in sequence)
Logic while mobbing or when caught offguard in a harder mob group:
Wave of Poison SLA Close Range || Glue Bomb Ranged >
Poison Strike/Shot >
Vein Freeze AOE || Cold Spike single target || Flash Freeze/Flesh to Gold if CC needed || Smoke Bomb SLA if displacement needed >
Vial SLA single target || Vial Smash AOE close || Bitter Frost Burst AOE ranged
High damage boss opener
Bottled Boost: Spell (shortly before battle starts) > Obliterate > Cold Spike > Vial SLA
Spell point conservation boss opener
Stiffen Skin SLA > Poison Strike/Shot (anytime before battle starts) > Cold Spike/Smoke Bomb SLA > Vial SLA
(Purple) Oh god I'm the last one living and everything has too high fort save to be controlled please give me all the tankiness as soon as possible I should never be in this situation but here I am
Glue Bomb/Displacement > Obliterate > BLOW EVERYTHING UP WHILE YOU HAVE +70 PRR AND ELEMENTAL RESISTANCES
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I've been enjoying Ice specced Bomber for soloing since Vein Freeze (aoe) and Cold Spike (single target) are no save 30% slows that make it easy to kite everything. Poison seems to be everyone's favorite spec but I have really liked Ice in particular - Ice for the no save slow/Vein Freeze and fire for the Cindersmoke/Flashbang combo that's some spicy stuff right there.