So I will come out and say that Yasuo is a problem. Now I personally do not have a problem because I play champions that stomp that champion into the ground. However, Lets get serious about this champion.
The mastery that is causing the Yasuo cries is Warlord's Bloodlust. Now this mastery needs to be addressed, maybe make the CD 4 seconds instead of 2 seconds. However Yasuo has to be addressed now. Enough of the Golden Protection. Yasuo will require a nerf to his passive. Keep the double crit chance, it is unique. But the crit stike damage has to be reduced.
Examples of champions that crit but do lower crit damage: MF ult does 120% on crits.
Personally I think Yasuo doing 120% on his crits because of his passive is fine and wont destroy the champion, just make him functional to fight for mid champions or top champions. He can still get to 170% crit damage with an IE, so no excuses from Yasuo Players.
Right now Yasuo is powerful, but he will get a lot worst when PD is no longer bugged and back in game play. Having 12% reduction of damage is huge! Slap that with the double crit chance for yasuo will make that item a god tier item for him.
So just do us all a great favor riot, hot fix this guys damage and save us all from being 100% forced to ban yasuo in preseason rank games?