Okay, this is actually really cool, and I'm gonna say I'm impressed.
You managed to lock my current and (by virtue of sole survivorship) flagship work's magic system firmly into "Magic as Engineering", though one could argue it slips into Art sometimes. I also noticed you placed Devil Fruits as Art but Haki as cookbook, and I would have thought of Dresdenverse as more engineering, but that's probably because we see it through Harry's PoV, who is more scientific than other Wizards.
To describe, in Solstice, spellcasters have access to one of the Classical Elements, one of the Dualist Aspects (called Light/Dark in the story, but inspired from yang/yin respectively), and the base resource of spellcasting energy, which is called Æther.
Everyone can manipulate unattuned (nonelemental) and unaspected (neither lightside nor darkside) Æther to produce basic magical effects, such as strengthening, mind reading, standard anime protagonist shit, and so on. Men pull Æther from around them and force it into a pattern whereas women draw it out from inside themselves and weave it into the desired form. You can infuse either your Element or your Aspect into the Æther to produce effects corresponding to that element/aspect, as well as completely no-sell any base-level Æther getting in your way. At the highest levels, you can infuse both into your Æther for something completely different, almost conceptual.
On top of this, people can utilize Spell Circles, which are diagrams involving geometric shapes and Futhark runes to essentially create their own magickal cookbooks. It is usually men who do this, because drawing such a circle permanently influences your Soul which changes how you shape Magick, and if you're a woman your central focus for spellcasting IS your Soul so you lock yourself out of the entire rest of the spell system. To counterbalance, there is a trick called Dominion which seizes all the Æther in the area so your opponent can't use it. Women are immune to this because their body, their magick.
... On second thought, I think my magic system is more "Magic as Art". You got me. Grats.
Please keep contributing to the world of authorial content. Humanity improves for it.
