Why completely remove Ekko's passive slow? Here's a better idea.
I think Ekko's passive slow is a huge part of his kit. It's what makes him sticky. It's what makes it so that he can actually do what he wants to do as a champion. I think that if you want to kill Tank Ekko and that's all you care about, this is a great change. It basically removes his effectiveness as a tank that can also stick to you and kill you over and over. However, I do think this change will be a huge hit to AP Ekko as well. I think the idea for the original Q nerf was spot on, so why not combine the two? Instead of completely removing the passive slow, why not make that slow scale with AP? That helps AP Ekko stick to targets and also allows tank Ekko to be a viable, niche build that isn't completely oppressive. IIRC, I believe Meddler said that they like Ekko being able to go tanky as a niche option as long as it isn't oppressive.