Yes, we get it. Thaumaturge is dark, with lots of dark knight and red mage spells at its disposal. They drain, absorb and enfeeble life.
Meanwhile Conjurers have 33 black mage spells primarily composed of elemental magic (fitting with Gridania's overt elemental themes). They may have healing spells, but they certainly pack a punch with their vast library of elemental nukes, there's no denying it.
People didn't chose the Black Mage job in Final Fantasies past because they like to absorb the accuracy and MP out of the creatures they fought, they did it so they could set them ablaze with Fire spells or alight them with Lightning spells. And yet, Conjurers were the ones to deliver this light show, not the Thaumaturge.
This is the conundrum; nothing else is.