[Snake]

50% or go home.

[Neus]

Eh, it's a cheap skill with a decent amount of utility already. I don't know if it needs a decent power boost on top of it.

[Lolzytripd]

imbue strike has no utlity.

It changes the element of your spear basic attacks to an element,

Everyone usually has 5-10% resist MINIMUM to every element thanks to stamps and sanc.

so you need at least 25% more damage to counteract this minimum elemental resist due to how the transitive affect of percentages

[Snake]

Well, it would have the 'utility' part if it applied the Flame's CC on-hit instead of some power over it, but it doesn't, it just changes damage type and that's it. If only Imbue Strike also applied a small Elemental Weakness debuff tied to the current flame's element, it would have one utility.

My suggestions is to make Imbue Strike a main-class only skill and on top of it, make it so an enemy would get a -15% elemental resistance to all elements (to a minimum of 0%) if you crit them.
(Or alternatively, each time a Critical Hit is scored with a melee weapon, the enemy gains 1 level on a debuff that goes up to LV6, on LV6, it transforms into the debuff: 'Nulled' from Magic Gunner's Null Shell for 4 rounds and reduces all of the enemy's resistances to 0%. But this sounds more like a potential idea than anything.)

It's true hell to score a critical hit as a Curate, so this would be the reward for it, I guess.