These suggestions are to streamline magic and make it more tactical and useful.

Separate Actions and Spellcasting.  Make the number of spells cast per turn or battle based on the essence level of the sovereign or Champion.

Allow champions to be imbued to multiple levels.

Spells:

Create a Direct Damage, Point Blank Area of Effect, and Wall type spell for each Element.

Give spells researchable levels.

Create spells to buff towns such as Increased Production of Food, materials, metals, crystals, make them last a # of turns based on caster INT or spell level.

Create Spells to convert materials, examples: materials to metals, metals to crystals. Higher spell level increases conversion ratio and amount.

Create spells to summon materials, metals and crystals. Higher spell level increase amount summoned.

Create spells to Buff a Unit's Elemental Resistance.

Create spells that give a unit Elemental Attack Damage.

Example Unit Elemental Buff spells spells:

Mark of Element ( Mark of Fire, Water, Earth...)

Level 1 Unit does added element damage.

Level 2 Increased damage and Adds Elemental Resistance

Level 3 Increased damage and adds damage shield ( Any unit attacking it will take elemental damage )

Level 4 Add Elemental based Effect, Fire - Damage over time, Water - Chance to freeze (Unit cannot counter attack), Air - Dodge Debuff or knockback, Earth - Defense Debuff.

Example Direct Damage Spells:

Fireball:

Level 1 Does Direct Fire based Damage

Level 2 Increased Damage and Damage over time.

Level 3 Adds Area of Effect and increased damage

Level 4 Adds Fire resistance Debuff and increased damage.

Iceblast:

Level 1 Does Water based Damage

Level 2 Increased damage and adds Dodge Debuff

Level 3 Increased Damage and Area of Effect, and Debuff Water.

Level 4 Increased damage and has % Chance to Immobilize Unit based on Caster INT and Unit Resistance.

Rockshards:

Level 1 Does Earth based damage

Level 2 Increased Damage and Area of Effect

Level 2 Increased Damage and Earth Debuff

Level 4 Increased Damage and adds % chance to Damage Armor. ( Reduces Unit Defense )

 Airblast:

Level 1 Does Air Based Direct Damage.

Level 2 Increased Damage and Area of Effect.

Level 3 Increased Damage Area and Adds Air Debuff.

Level 4 Increased Damage, Area, Debuff and adds % Chance to stun Unit (Making them loose a turn) or action points

Point Blank Area of Effect Spells:

Level 1 Does damage to any unit around the caster.

Level 2 Increased Radius and Damage

Level 3 Increased Radius and Damage, Adds Debuff.

Level 4 Adds Element based Effect. Example: Fire = Damage over time, Air = Stun, Water = Immobilization, Earth = Reduced Defense.

Walls - Effect tiles with Elemental Effect with duration based on Caster INT

Firewall:

Level 1 Creates a Wall of Fire that does damage to any unit on it per turn.

Level 2 Increased Damage and area.

Level 3 Increased Damage and Debuff.

Level 4 Increased Damage, Debuff and add damage over time to any unit that passes through.

Icewall:

Level 1 Creates Barrier of Ice that must be destroyed to pass.

Level 2 Increase area of Wall and Health.

Level 3 Increased Area of Wall and Health, any unit physically attacking it takes Water damage.

Level 4 Any unit attacking it has % chance to become frozen in place for a # of turns

Rockwall

Level 1 Creates Barrier of Rock that must be destroyed to pass.

Level 2 Increased size and Health

Level 3 Increased size and health adds attack debuff to any unit attacking it.

Level 4 Increased Size and health, any unit physically attacking it takes Earth Damage

Windstorm

Level 1 Creates a windstorm that does Air damage

Level 2 Increased Air damage, Area and adds Dodge Debuff

Level 3 Increased Damage, Area and add Air Debuff.

Level 4 Increased Damage, Area and adds % chance to stun unit (looses action points or turn)