Irelia's E is a flawed ability that punishes the opponent for making skillful and smart trading

The ability makes Irelia extremely difficult to snowball off of while she's behind and still remains very oppressive when she's ahead since she only needs the slow to kill you if she's already beating you in lane. The ability is balanced as if it only has a slow, which in turn makes it have a very low CD and mana cost at all ranks. This makes Irelia's E one of the strongest abilities in the game and makes her not only frustrating, but extremely difficult to deal with unless you are numerically superior to her in every way to the extent that you can outduel one of the best duelists in the game in their most favorable situation.

I propose making it not slow at all and only stun so that you people who play her can maintain your "ability theme" while also making the ability not perfect for every situation and making the Irelia player choose between damage/cast time or saving it.