Really, if you guys are having this much trouble with his ultimate playing too much of a role in pro-games, why not simply nerf the ability itself? Instead you decide to nerf his potential as a solo-laner which goes against everything you've contemplated a couple of weeks ago.
The guy already received MASSIVE nerfs to his only offensive ability before (he lost part of his damage, sustain and slow on his Q) and now you're even nerfing his capability to tank damage (see his latest passive changes on the PBE). In his current state he's literally just an ult-bot, and even that ability comes with a huge price - usually the loss of his tower the moment he leaves lane to help someone. And don't get me started on his complete lack of waveclear, he's just extremely dull to play as.
Wasn't your original plan to give him some more laning power while increasing the cooldown of his ultimate? He's already a very weak solo-laner (just look at his Solo Q performance) and yet you feel inclined to balance the game for an extreme minority that apparently knows how to make this sad excuse for a ninja work.
How about you finally fix his taunt-hitbox? His model can collide with the opponent and yet the effect simply won't go off, that shouldn't even be possible.