Akali, Irelia, Yasuo, zed, Kat, fiz, Pyke, (Zoe).
So lets be honest, if to you are facing one of these champions, the chances are you are not having any fun. Unless, maybe, if you are using one of these champions.
The issue with the above group is that due to their kit design, there will never be "balance". They will always be nerfed into the ground (Akali) or stupidly strong (zed).
Simply put, the new age of league, where every champion worth his salt has a dash or blink, those with multiple are inherently unfun to play against.
We've all been there, that pykes on 30 hp, you flash away from his ult, go in for the kill, only for him to press 2 buttons, disappear from sight before dashing through a wall gone forever.
Or,when you corner that Irelia only for her to spam one button, become faster than the human eye can detect, and disintegrate your health bar.
The reason these champs get banned isn't because Akali hits like a truck, or fiz can 100 to 0 you in 2 seconds. It's because they can press a button and negate any counterplay.
And why do these champions have these moves in their kits? Simple, it creates "outplay potential" which feels good to pull off, and looks better on the TV (laptop monitor) during tournament play.
Ultimately the state of these champions, and league, is getting worryingly close to unfun. With a power creep slowly making immobile champions redundant (sorry jhin) and forcing new champions to be zipping accross the map in order to keep up.
The Development team need to take into account the experience of both players when designing/ reworking a champion. Sure make the champion fun to play, but not a the cost of the enjoyment of the opposition. Zoe alone proves this is not a priority at the moment.
I hope in the next year or so we get interesting champions who can feel satisfying to play & fight without having them blink accross the map like mediaeval dragon ball Z characters.