nice designs, except Tecna.
I mean, that's a nice design, but she's not Tecna
Bloom doesn't usually get angry, but when she does she goes full WRATH OF GOD-like(in character, not necessarily in powers).
Maybe make it so her powers go haywire as metaphor for people with anger issues.
Stella is the usual Valley Girl Airhead Bitch, putting effort mostly on teasing boys... unless one of the few things she cares about are involved, then she turns into Unstoppable Fairy Terminator.
Give her 1-2 uncharacteristic interests she's a utter nerd for, something very niche like, dunno, neolithic Earthenware?
Layla\Aisha should have a dislike for impositions
Tecna doesn't usually notice her social faux pases, and generally doesn't care much, but when she does she feels it very strong.
says, fashion is a strong selling point. Have them change from their regular clothes every other episode