Quick problem: spells as demons

Yup. What it looks like is just FX (with the occasional bit of side detail, like a fireball setting everything on fire instead of just blowing it up or disolving it or such).

If you wanted a school kinda thing, then somehting like Ron already has in the main Sorcerer book (MSB) in the form of the various factions. Each has a special style of sorcery and demon they tend to summon. It tends to be more loose here, but with some fairly hard and fast style descriptions it will focus what kind of spell/demons one sorcerer can manage over another.

If I want somone from The order of the Flame, his spells will be fiery or at least have a fiery FX component and typicaly call for the sacrifice of flamable substances (rare oils, woods, paper dolls, hair etc). His Special Damage spells always involve fire or heat, and his Transport spells are fiery gates to other places or great wings of flame. His demons are fire elementals. A Possessor might cause the host to suffer fever and sweat constantly.

If someone wants to define their sorcery very tightly like this, I'd grant bonus dice when they describe it really well and play within the rules they create for themselves. If they straw from their own definitions, I'd levy penalties.

keep the good stuff coming!