CertainlyT is a good designer

I notice how you didn't mention "play against".

CertainlyT is good at making interesting champion gimmicks.

He is bad at making complete champion kits with actual weaknesses to balance their strengths.

I was "certain" that you were going to say "Said no one ever."

you jsut forgot the 3rd and evenly important thing: fun to play against. And no, his later Champs don´t deliver on that at all.

and champions that will double suicide rate when you play against them? Problem with CertainlyT champions has never been "being fun, interesting and entertaining champions to both play and watch." or the opposite, it's the fact that these champions are extremely toxic to face. Mostly actually. I personally don't have much problems with the other champions he designed : the real problems with those champions were their numbers at release, not their kit (though some might argue Yasuo's windwall and low cd dash were too much). But Kalista... Like , come on, one dash on every auto? A champion that can not be ever touched by quite a part of the champion pool? This is not healthy. Yes, there are counterpicks and shit. But a champion that counters you so much that no matter what you build or do, you can't reach her if you play a kiteable melee champion ; is toxic. (I consider a bit toxic in that way too, but at least you can her ult which makes up for some couterplay)

He is not a good designer. Yasuo and Tryndamere are fucking atrocities and are annoying piece of ***** to play against. It's like he puts every kind of ability he can think of and slams it into a kit, then adds on free armor pen or double crit or whatever insane freelo enhancement as an added bonus and pronounces it ready to play, when all it really is a fucking OP champ that everyone hates to play against. The only good champion he's made is Zyra.

Honestly agree with you thresh yasuo probably one of the smoothest champions to play in the entire game just feels right.

... Kappa. (you forgot that from your post)

No, he's not. And even I can design a champion like that: Have a skills that deals over 1k dmg, have a skill that is a global stun, have a skill with a global teleport etc. There, now we have a fun, interesting and entertaining champ.

But is it balanced and healthy? Nope, not at all.

He makes champions that are fun to play.

They are not fun to play against.

That's not 100% healthy design.

He's got good ideas, and he does get the theme of a champion down into their kit, but he does somewhat overload a kit and/or make them unfun to play against. But nobody is free from criticism, and the guy has his flaws.