BatteMage Vs other Mage Vs Bosses

I feel battlemage on main bosses is very weak........ while other mage get full dmg bam only do half dmg
the only other mage that is at battlemage level is Bishop..

Here the reason.... When attacking Boss such as ( Magnus / Hillia / Cygnus / Pink bean )
Battlemage only do 50% of it their dmg to those boss cuz these boss has Physical Resistance and Battlemage is the only Mage other than Bishop that doenst have Elemental reset or 100% Resistance Ignore

Fire / Poison - Elemental Decrease

Ice/Lightning - Elemental Decrease

Evan - Elemental Decrease

Luminous - 100% Resistance Ignore

BattleMage - None

Bishop - None

I think bam should get a 100% resistance ignore just like lumionous so it too can be the same rank as the other mage