Keep Fire, rename Fire II to Fira, rename Fire III to Firaga. Keep Firestarter as-is. All Fire Spells and Flare now inflict 100% Fire damage.
Keep Blizzard, rename Blizzard II to Blizzara, rename Blizzard III to Blizzaga. Cause Blizzard III to now inflict "Slow" on all affected targets for 8 seconds. All Blizzard Spells and Freeze now inflict 100% Ice damage.
Keep Thunder, rename Thunder II to Thundara, rename Thunder III to Thundaga. Change Thunder and Thundercloud around so they operate backwards from how they currently act. In this case, Thunder spells would do full damage without any natural DoTs, and Thunderstorm would enable a chance of causing the next Thunder spell cast to create a Thunder DoT on the enemy. All Thunder Spells and Burst now inflict 100% Thunder damage.
Remove Astral Fire/Umbral Ice as buffs. Instead, add two toggle buffs, "Astral Annihilation" and "Umbral Meditation", which would act precisely the same as Astral Fire and Umbral Ice, but works on any spell cast rather than being dependent on Fire and Ice spells. These toggle buffs would completely replace "Transpose".
Change Flare to maintain an AoE field, inflicting the same amount of damage as a Shadow Flare field.
Change Freeze to be as powerful and cost the same amount of mana as Flare, and have it create an AoE field that causes all enemies inside to be afflicted with Heavy and Slow.
New Spell: Burst. Same amount of damage and MP cost as Flare, have it create an AoE field that causes every enemy to be under the "Chain Lightning" debuff, causing a DoT dependent on how many enemies are inside the circle and how close they are to one another.
Add three new spells to THM Arsenal:
Emblem of Nald'thal: Target's Fire Resistance is reduced by 50% for 20 seconds. (120s cooldown)
Emblem of Halone: Target's Ice Resistance is reduced by 50% for 20 seconds. (120s cooldown)
Emblem of Rhalgr: Target's Thunder Resistance is reduced by 50% for 20 seconds. (120s cooldown)
Add 1 new spell to BLM arsenal:
Insignia of the Black: User's Fire spells inflict "Emblem of Nald'thal" on all targets, Blizzard spells inflict "Emblem of Halone" on all targets, and Thunder Spells inflict "Emblem of Rhalgr" on all targets for 30 seconds (360s cooldown)