A simple change that would help Illaoi immensely

Make her W a single-target spell that applies on-hit effects.

Currently, her W requires auto-attacking to use it. It's fairly clunky. It's easy to CC her and prevent her from even auto-attacking once when the perfect window arises. It's easy to accidentally cancel her W's animation and completely ruin her moment of power. Even a 5-man ult is completely useless when you can't W during the window of opportunity created in the first couple seconds or so after her tentacles come out.

Changing her W to a single-target spell that applies on-hit effects (akin to Fizz Q) would make her much smoother to play, allowing her to properly take advantage of her strengths, while still allowing her opponents to meaningfully play around her weaknesses.