No, it doesn't need to be toned down. It's meant to be just a little stronger than your average spell and personally I prefer ice storm
I'm practically immune to laming aura, I don't know how many others have high fire resist but even without it it's quite easy for you to also cast a spell, run away or kill the person. I mean..they have to get close to hit you, cast a few large snow storms at them and if that doesn't kill them then you can still attack them making the odds more than even.