Pet Tank could be interesting if implemented properly. Or heck, let's just say it, what about a "Stand" like tank, where their main arm is a "Synchro Orb" and the whole gimmick is it allows them to call upon the spirit within them to tank for them, while the user might be physically weak, their mental strength allows them to fend off powerful strikes against them. <_< And for fun the tank would do poses that cause the spirit to act rather than actual engage the monster themselves.

Healer, I would like to see a Chemist like healer, using mixtures combined with aether to create/hold different healing spells. So they could prepare different concoctions but preparing them reduces their max MP so it would be about knowing which concoctions would be needed for the situation while managing MP to use maybe instant spells that rely on TP to use as well. So while a Chemist wouldn't have a "casting bar" for any "spells" they would be limited by their TP, so if they spammed to hard and ran out of TP, their ability to heal quickly would be lost. Chemist "weapon" would be a "vial belt" with a variety of different looking vials and colors to depict the different type of attacks/heals they could perform. They wouldn't throw the vial but rather pop it open spray it out with their right hand then use the aether in their left hand to activate the concoction effect.