I agree with you that legendary skills ought to be stuff of legends. But I also agree with Davros that 600 damage is excessive.
The problem lies in the fact that a player with 2400 baud can (Even with the equilibrium time delay) kill a player with 1000 stam by doing just 2 handburns, at 1200/75 it will take me (If I were able to cast it, which i can't) MUCH longer to perform the chant, or to react to the offence.
I would favour a system where the handburn still does about 100 damage, but the damage carries on happening, like bleeding, you are badly burnt and the better the mage who cast it, the longer the spell will keep working on you until you get an animist to heal it or a herb put on it. 600 points damage outright is over the top.
Likewise for the healhand, you cast it, get healed your 207 points, and 20-30 seconds later obtain another 100, then another 20 seconds later get another 50 and so on, the higher the level of charming, the longer it goes on for.
Dalamar. (Who has little to say as he cant cast even paltry enchantments)