I think the main yuumi problem is the fact that her projectile is not a dodgeable skillshot like every skill shot out there. the fact that unless its low elo and the player cant use his champ, she always hits her q and manages to slow you its a real pain to deal with when you are trying to run away from them. All she needs is for her to be in range and you are basicly dead nomatter how good you are at dodging skillshots. I think that should be fixed becouse it gives no chance of counterplay and be given some sort of pattern. Even if its a complicated one ill take it at this point bc outrunning a yuumi is impossible now.
That or we can atleast stop the projectile from jumping walls or smth, so when we flash we know it was worth it.
Edit: riot keep it up with the downvotes for no reason. literally no one here give a valid reason yet somehow 5 random people (aka the same for the whole forum posts) manage to downvote it.