How to make Ahri's W an actual ability

Revert last nerf to her W in season 6 or 7. Give back her ap ratio again. Meaning, to bring it up from .3 to .4 ap ratio.

Her W was nerfed because her Q ms gave her immense survivability for the early game while also having some scaling with w, which Riot nerfed. Now that she no longer has that safety, she should get her W ap ratio reverted.

The current rework was supposed to be a revert, and her W is an horrible ability which has no scaling and no powerspike. Giving it some ap ratio will at least make it relevant somewhat for lategame where Ahri is really bad in.

If that is too much, then reverting the last charm duration buff or mana cost is good, or both. That never was needed, and made her way too forgiving for no reason.