The thing with fire is not that it is overpowered, but rather that it is "Complete".
By somewhat coincidence it has everything an element really needs to touch through all bases and that is what makes it terrifying and ridiculously good.
Fire's cards cover such a wide range of utility that it makes it incredibly difficult to counter.
While most elements focus on either "Maining (Death for example)" or "Support (Aether)" Fire has access to both.
This card spread makes countering fire extremely difficult.
1. Immolation
This allows fire to gain instant quanta, which increases it's speed by a large margin compared to other elements, while giving it access to other cards with ease.
2. Deflagration
Cheap PC is incredible. While Pulverizer and Butterfly effect are arguably more powerful, 2-1 quanta cost is amazing not because PC on its own is strong, but because shields and weapons are so powerful. Cards like Dimensional Shield, Dusk Mantle, Eagle's Eye, Discord, etc. can win games on their own, which is why Deflagration is such a powerful resource.
3. Rage Potion
Rage potion is an incredibly good form of single target CC. In a similar niche as Lightning, it can seriously shut down the damage from a large amount of decks.
4. Fire Bolt
This is one of the big things that makes fire incredibly powerful. With enough quanta you can use it to kill nearly every creature in the game, and it gives Fire Access to alternative damage. Since one of Fire's bigger weaknesses is how easily its creatures dies, near unavoidable damage circumvents this and makes it difficult to counter.
5. Fahrenheight
Fahrenheight coupled with Fire Bolt means that you can never have too much Fire Quanta. This makes Fire Stall an extremely stable deck because it turns every card into something useful. While in many other decks you can have under or overpillared draws, in a deck designed to simply get as much quanta as possible and survive at the same time makes this very difficult.
6. Phoenix
This is the recent addition that made Fire complete. While before it's creature damage was very unreliable because of how easily they could all be killed, Phoenix remedies this by giving it a near indestructable mid-range attacker. This means that it's biggest weakness is covered and it allows fire to touch all bases
With strong control all over the field, speed, powerful/difficult to kill creatures, alternate damage, Fire is difficult to beat, simply because of a few key cards that let it touch all bases.
But the cards on their own are balanced. It's just the fact that you can access them all so easily that makes it so difficult.
Rather than directly nerfing fire, giving other elements more options will make them be able to compete.
