Illaoi's W is really buggy and cancels a lot
When you try to auto somebody with your W on and get CC'd during the jump, you do no damage and the W is consumed.
When you click to auto somebody and try to move at the same time, she just doesnt auto but instead starts the animation then stops, starts then stops.
These might seem small but she cancels or loses her W so much which causes her to lose out on a lot of damage and reliability.
I'd say giving her W the same treatment as Vi E from a few patches ago in not cancelling would be really helpful.