I'm just going to get straight to the point, here. A wall that breaks projectiles seems perfectly fine to me. He's a melee slayer guy, and if he's jumping feet first into danger, there's nothing wrong with a tiny bit of safety. But there are two main issues that come with it that can be changed.
#Firstly, his wind-wall is _thicc._
I don't mean it's long, but actually thick. It's wide enough to stand in, which he makes people do. He can put his wall on top of the enemy ADC and use it as a literal Teemo-esque blind until the ADC walks out of it. it's kind of like Grave's smokescreen, but without the range, slow, or debilitating nearsightedness it causes. So if you're trying to engage on him, he can run up to you really close, lay it down, and get some free harass on you, all while you're forced to run away to even manage to break his shield. If a Caitlyn, Ashe, Jinx, Miss Fortune, etc, is trying to ult him, he deserves to be able to block it with a well-timed wall. But if a ranged champion is simply trying to use an auto attack, putting a wall right on top of them to banish them from using any attacks or skill-shots is just cruel. INVERSELY, once the ADC walks away from the wall, Yasuo himself can stand inside his windwall, attacking freely whilst negating attacks from all sides. Like, ew.
#Solution: Make the wind-wall thinner.
So Yasuo can't abuse its massive hitbox.
#Secondly, when Yasuo casts the windwall, it shoots out from within him as a cone.
Why is this bad? Well, it turns his mere "Wind-wall that blocks abilities" into a "Free spell-shield that then turns into a wind-wall that blocks abilities." You've seen YouTube videos where a Yasuo blocks a Thresh hook by casting his wind-wall *sideways*, haven't you? It's because of how his wall is designed. Since it casts from within him, any skillshot that's **almost** about to hit Yasuo will get negated, as if it did hit him, but Yasuo just used a cleanse to physically push the projectile away from him. It's too good, and it's too safe.
#Solution: Make Yasuo cast his wind-wall from left to right, in the way Victor's E does.
Give it the same length, distance and parameters that his current wind-wall has, but change its summoning from coning out from him to coming in from a side. You can pick the side; I don't care. Probably from left to right, because that's how he would naturally cast it when unsheathing his blade. Aesthetically speaking, of course.
Sooo, what do you y'all think?