Well people want destruction magic damage to level with the character. But i don't think that the all your destruction magic should level. just the spell you use. To a max of maybe 200-300% damage. So if you train the c r a p out of flames it'll get better. But not all your destruction spells
Whatcha think of the idea?

I agree to an extent. I like the idea of destruction scaling with levels, but having to train each element individually would lead me to playing the violin on my wrists.
Too much effort
But the scaling idea is pretty nice

Well it goes with the theme of the game you are who you play. If you like flames, flames will get better.

It makes sense that if you use a certain spell more you would get better at it. But it would make it harder to level up the other types of destruction spells. I guess since you have more mana as you progress, you can do the same spell more often.