Are new spells needed for the 4 schools of magic?

I completely agree. For demons, add the ability to summon demons as part of summoning magic, including not only the canonical ones but also some new ones. For necromancers, add the ability to resurrect slain enemies on the battlefield as undead – all of this should be integrated into summoning magic. For magic used on the map, create something like a "fall into a dungeon" spell – when the exit to the dungeon is far away, but you need to go down. I have a ton of ideas... I wish at least 10% of them could be implemented!