Throwing down:

Sylph of Doom or Prince of Life for Ly'lac. Staving off the inevitable until eventually it can be broken apart.

Maid of Rage for Yiffy. She's quite literally made of narratives and rage from a literal perspective.

@alexArtForm Thief of Doom for Tavvy would make the most sense in this case. He's willing to take the misfortune of others on his shoulders and make the most of it, and he's a good caretaker to make sure others get rest so they're at their best like when he asserted that Harry and Vrissy should make sure to eat the nuts and don't just pick out the parts they like.

Knight of Heart for Harry. I suspect he'll end up being the star of the show even if not the only one. While he's clearly got John's and Roxy's cavalier attitude and realistic outlook on life I figure he's got some things he still needs to get off his chest too from time to time. Expressing himself would be perfect Knight of Heart as someone who serves identity and passion, given his thespian qualities and proclivities toward expression through clothing. I figure he and Tavvy are most primed for being the caretakers of the group that keep everyone grounded when everything feels utterly fucked. With Tavvy saddling burdens even when the others refuse to let him take it on alone as well as making sure the group gets time to rest so they can grow properly, and Harry reminding them of the good aspects of life that are worth fighting for.

Vrissy I have no idea. Something Mind makes sense but I figure the biggest thing of all is that Vrissy's going to have to learn who she is outside of Vriska's shadow and become her own person, which means it'll likely be something regarding acquiring perspective over time, and understanding who she is by that merit. I'm guessing Heir of Mind or Mage of Heart.