Isn’t that basically all of her cosmetic though ? Flaming hair, Lanterns , red and gold cloth, charred copper skin, key iconography (Aqshy’s symbol is a key)
I do like the staff clutching a Jewel.
Overall though, it looks to me like this very picture could’ve been a source of inspiration in the creation of Sienna. The lanterns by the head for example.
Sienna with a more red flowing robe and the spell tome hanging by her side. I guess I can see sienna in something more regal. Perhaps if her final class involves something royal, like a court mage? I have no idea what the lore of this game involves though.
There are court mages (though I don’t think they would be called Royal, since the Empire doesn’t have any Royalty, but work on Elector Count and an Elected Emperor, while Tilea has something else which is escaping my head), some were named and for example Gelt can be considered as Karl Franz’s Court Mage, Advisor while still being the Head Magister (Whose exact title I forgot, but it’s the one that has the Staff of Volan after all the head nerd have finished playing whatever the play to decide who is the uber-nerd)