Conjuration requires you to do summons to do damage (either weapons or creatures), Alteration is defensive in nature as is Restoration but can be used to improve other styles or schools and Illusion is the "wild card" or "utility" school.
The current magic however means that of the 3 "combat" spell schools;
Conjuration pwns, Illusion pwns, Destruction..................gets pwned
This is a fundamental flaw in the game design that needs Bethesda to sort it out. We should not have to rely on mods to fix glaring issues like this. The mod also in no way useful for console gamers. But hats off to the peeps making it.

