I like these mechanics though this does get a bit deeper into demonology (potentially). However needless to say the same thing works with the celestial and ‘in between’ spirits too.
The visualization of the sigils is very Giordano Bruno / Raymond Lull …
It could certainly be a whole ‘nother type of magic. I think you could do 4 or 5 books the size of Superno on this kind of thing and many others, and I may end up going there (part of the way).
I cold collect spirit names, of course many of them are in Pseudomonarchia Daemonum and so forth. There are some other directions you could go into –
Norse (which continues into the Renaissance with books like the Liber Runarum)
Celtic Magic – as derived from the various late Iron Age sources, Fenian cycle et al
Cunning magic – which has rich traditions all over Europe but is sourced mainly from various 19th and 20th Century surveys, as they mostly didn’t write books, but there are some sources like the Merseberg incantations. And mythology like the Kalevala.
Greek / Classical magic – Natural Magic following Ptolemy etc. down to curse tablets et al
Neoplatonist magic – Both Classical and Renaissance version
Arab and Persian – Takwin, Jinn and Devs, Peri and Efrit
German / Folk – The German stuff sometimes makes it into period books
Soldiers magic – Bellifortis down to the various sword charms I have in the book, but it goes way beyond that
Hebrew / Kabbalah – Name and number magic, golems etc., angels (Mal’akh, Seraphim)
Renaissance Magic ala Agrippa, Ficino, Paracelsus etc.
Elizabethan Magic ala John Dee
And of course, the type we are mostly referring to here, the Ars Goetia, Early Modern Demonic magic.
And that’s just for Europe! It gets wilder the further afield we go….