You unleash a ray of crackling arcane energy that destroys a magical effect created by an opponent.
I'm guessing that Break Enchantment might still be in to deal with these kinds of controlling spells but with a narrower focus so it wouldn't cover all zones and ongoing effects.
Charm was traditionally a long-term spell and could lead to interesting role playing. I'd be happier with a save once per day unless the character is conflicted in which case they'd get a standard saving throw each round. So in the middle of combat against the charming wizard you'd get a save every round but in ordinary circumstances just once per day. This method means that long term charms can't be used to recruit cannon fodder because the charm will likely break at the first sign of trouble.
The question is should the daily save be a contest rather than a normal saving throw? Or put another way, should a level 1 minion charmed by a 17th level wizard be as capable of breaking her influence as a level 11 cleric? Personally I think a Will Attack vs Will Defence contest should be used for the daily save.