Please do not make Katarina an AD champion
I can understand wanting to make changes to her but why do these changes have to come with a switch to AD scaling? She's an AP assassin, her fans like playing her like that. How does switching her scaling to AD do anything to make her playstyle more healthy or engaging?
As someone who loves Katarina, the idea of jumping around to enemies every 3 seconds with Shunpo so I can annoy them with auto attacks one by one does not appeal to me one bit. You haven't even made AD Katarina just another viable build, but you've destroyed AP Katarina too. The only damage she has now is Death Lotus.
This is such an unnecessary change. She will play completely differently to how her fans like, she will build completely differently to how her fans like, and her laning phase is destroyed for the sake of... being a tower pusher later? Not worth it Riot.