The passive, Q and R all seem both too iconic and simple to screw with, but that leaves the wind wall and the dash.
While a wind wall defensive tool is as much a part of yas as 'hasagi', in its current form it seems a toxic 'get out of jail free' card. How about giving him, maybe 3 or 4, dashes then a long cooldown. Each dash would also have a smaller, very short duration wind wall with an ordinal component.
That is to say, he dashes forward and gets the wall on his right, for the first dash. The second dash gives a wall on his left. The third, wall behind. Make the wall pretty much just the length and duration of the dash. A couple seconds to reposition between dashes, and like a 10 second cooldown for the E.
For the W, a spin in place kinda move. One hemisphere a wall close to him, and the other hemisphere a slightly bigger radius of damage. I'm thinking of Fiora's Riposte as a parallel ability and "Lone wolf and cub" 'zanbatao' for a visual effect.