How to fix Yasuo in my Opinion
Passive(Way of the wandererZ) - Just remove the x2 crit chance. I mean seriuosly the champion is not going to break if you take out the x2 crit chance. He's just going to end up having to build proper fighter/bruiser items just like any other fighter/bruiser champion out there.
Q(Steel tempest) - I think once you take out the x2 crit his animation cancel q won't even be noticable anymore. Maybe only in laning phase.
W(Wind wall) - Instead of it bieng a few second wall that blocks everything make it like fiora's riposte where he quickly slashes the air like he already does and just blocks the next projectile if timed correctly.
E(Sweeping blade) - I got no problem with this ability. It's such a cool ability to have =D
R(Last Breath) - You could possibly lower the 50% bonus pen to 25% or just completely replace it with bonus damage against targets that got ulted.