It's laughable how poorly balanced Yuumi is
We know that someone at Riot looked at Yuumi's kit, her numbers, playstyle, effect on the game and said without a shred of irony "Yes, that's totally fine, release her as is." Let that sink in for a bit.
Her Q's range is massive along with damage that isn't really anything to be sniffed at for a poke. It can also chase you. Lol.
Her W allows her to dash however many times she wants as long as your teammates are close enough, making pickoffs hilariously easy. Don't even get me started on being untargetable.
Her E has two charges for really no reason at all, making it one of the strongest burst heals in the game. Don't know why it isn't one charge with a lower cooldown.
Her R has a gigantic area of influence making it functionally impossible to not catch at least 2 enemies in it, unless you messed it up big time.
When I play Yuumi, I see a character that's designed to be idiot proof. From the games I've played on her, It is unbelievably hard to fail in your role as support with her. The only thing that could cause her to fail is her ADC being absolutely god awful, which is out of your control anyway. We shouldn't have to beg Riot to nerf this or nerf that when this kind of thing quite obviously needs a nerf. This isn't fun to play against. Get it?
Inb4 winrate that no one cares about anyway.