oh oh, quite a few

ely- instructor guard, he realizes that his home is with rhodes and that he wants to help shape future generations, like his new children.
phantom- some combo of reaper guard and dollkeeper, a version of him that's decided he's tired of the wine god's control over him and manages to overcome it................... said moment is thanks to a certain fish. maybe. maybe.

shamare- i think core caster, becoming like a 5* haze where she still debuffs but has a higher attack stat. more of just growing into a more advanced role.
amiya- lol. lmao.
absinthe i see either as an arts defender like you suggested, but i think likely because of taking inspiration from her Bird Dad, maybe a flagbearer?