[B0rsuk]

Regular sorcerers are your best researchers, I think. I select those with 2 fire to be my combat mages. You can research Evocation3 for Fireball, then Fire Cloud and Falling Fires. You're going to need Phoenix Power for the last 2 spells (Conjuration... 3?). Both spells are great against swarms.

I research early Alteration spells for access to Barskin and Eagle Eye.
Once I'm starting to use Black Sorcerers, I research Stoneskin and Ironskin. If enemy uses lightly armored units,black sorcerors can cast Summon Earthpower and Blade Wind.