Are MCH'S meant to be weak?

[SolumAus]

Hi, First time posting here, I've played FF for two years but I'm still extremely noob at the game, not utilising alot of classes and damage.

So I recently unlocked HeavenSward today, super hyped to try out AST and MCH, but when I was doing the first trial I found them to be ungodly weak, like even a white mage at level 30 using Stone would do 2-3x more damamge, than what I was doing to the monsters.

Am I not using my skills properly? Am I meant to have better gear?

Sorry If I posted this in the wrong thread.