Yasuo Tweak Idea
What if we changed his passive to grant slightly increased movement speed instead of a shield? It would still help him avoid poke in lane but require him to actually dodge skillshots, increasing interaction and skill expression while decreasing frustration.
This tweak could go further. What if we required Yasuo to have, and expend, a full flow meter by pressing his R key to launch a tornado instead of using his Q three times in quick succession? Learning Last Breath would not be necessary to launch the tornados, of course. This change would let Yasuo choose when to engage and to use the tornado for waveclear or poke instead, while reducing tornado spam.