I miiight make a Fairy secondary character. But I’m not sure 



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What were you thinking for the elemental affinity? I would suggest Air, because then they could eventually fly around as they're teleporting that would also pair well with telekinesis.
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Okay, cool! Though, you'd still be attuned to one of the four elements, so feel free to toy around with that. And for the appearance altering part, you could always have that as a racial trait, similar to a Changeling or a Skrull.
Shit, I totally forgot about that option before. Racial abilities not tied to magic. So, as long as it's not too overpowered, everyone can feel free to add racial traits to their characters, such as wings, darkvision, heightened senses, form-shifting (such as lycanthropes), etc.

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Telekinesis would be covered by Universal Magic, and you could flavor some of the elements to cast illusions, such as using water vapor/moisture in the air to reshape the flow of light through the atmosphere around you, kind of like casting a rainbow. Or you could use air itself to reshape the light. Or you could have that covered by Universal Magic as well by using mild telepathy similar to the original idea for Cerebromancy.

I think the choice between these affinities and the D&D schools would largely hinge on one of two viewpoints in deciding how magic is built fundamentally.
1) the utility and general effect of a person's magic is intrinsic, and they learn to express that form through various elements or "lenses." (D&D system) Someone born into Evocation would be able to utilize that through blasts of fire, lightning, ice, force, sound and so on, but night need training to branch out to Conjuration before they can summon anything.
2) the flavor of one's magic is intrinsic, and how they refine it to specific uses is learned (your original system and mine). Someone born of pyromancy can shoot blasts of fire and summon fire elementals, but might need training to branch out and perform those same blasts or summons for lightning, ice, force, sound and so on.
Personally, for a non-stats non-dice rp, I prefer the 2nd method.