Brief cooldown on Kha'zix E?

Granted, I'm not a Kha'zix main, but if I'm stunned and mash E to leap on someone and it kills them, I do a second leap in place and then it goes on cooldown. The animation looks really wonky too. I think it would be a buff, and not a nerf, if a very brief cooldown was added to his E when it resets to prevent this.