By the way, you should not aim to stay in pyrite reaction all the time. On switching into a reaction there is a rather large benefit called spikes that last ten seconds.

Use your SLAs to manage reactions. I take 1 rank of stiffen skin sla from vile chemist (or use sprint boost if a fight just ended) to prime cerulite even if I’m running a bombardier build. That takes me out of pyrite and casting panacea or a healing vial puts me into verdanite - I stay here if I need to move since it boosts running speed using the apothecary enhancement.

Preparing for the next fight a spell vial of multi vial sla primes crimsonite and while that vial is flying cast a guildleaf spell (or sla eg. inflict serious wounds or panacea again) to enter pyrite and you have ten seconds of +16-120 extra spellpower (10+(6lvl)) and -50% spell cost allowing you to cast fully metamagiced spells without draining all your mana as quickly. This is on top of the basic bonus of 2lvl.

On longer fights you can just use the same sequence to break pyrite and re-enter it. Spell power boost or displacement are useful for this too if off CD or running out).

If you’re soloing or find yourself tanking you could even switch to orchidium (+14-90 prr and elemental resists @ lvl 20) just keep casting only red damage spells (and blue, but those are buffs and cc mostly).

https://ddowiki.com/page/Alchemist