PSA: Nerfs are to improve balance, not to remove identity
Every time a nerf comes to PBE I see people complain that "Rito is nerfing the wrong abilities". recent arguments revolve around: "Fiora should just not do true damage" (when that is the sole purpose of her kit)
Nerfs are applied to reduce a champion's strengths, not to remove their kit. In most cases, instead of directly reducing the power of the prime aspect of a kit, Riot instead wants players to either put more risk in to playing with that kit or make the choices related to such abilities more important. These complaints from players who are annoyed by a specific aspect of a champion, and instead of learning to play around it they simply yell about how OP it is. When the champion as a whole gets nerfed, they still complain because they don't see a direct numbers decrease on that one ability they hate, and they neglect to see the opportunities for counterplay afforded by specific ability decreases.
TL;DR: Children need to stop complaining about bad nerfs when the fact is that champion as a whole loses power.
If they nerf her damage she'll be just a cocoon stun bot, and than you realize that cocoon is just a single target stun and that it's not easy to stun someone you want in the middle of a team fight because someone else or a minion can block it making you a sitting duck.
If he doesn't have enough damage and isolation that actually means ISOLATION he isn't able to pull off that damage and assassinate his target. Why leaving an assassin with such a great utility he can't use at full potential because he can't isolate his target for max damage? I mean....he can achieve that isolation but ONLY if squish is dumb enough to stay 600 miles away from his team mates.
What is the point of being a stealth predator like hunter with burst damage if your enemies can SEE YOUUUU like they are Saurons from LOTR. Do you know what's the problem with Rengar? Not his damage nor his Stealth but his overall wrong identity. Dont get me wrong, he has identity, good enough but completely wrong for that type of kit. Rengar should be a fighter who can be able to 1v1 any squish but not in 0.28 sec. Only 2 things in Rengars kit are special for him, his passive and his ultimate, everything else can be reworked into something fighter like and believe me, with unchanged passive and ultimate Rengar would not lose his identity but will be much more healthier and not just "Go in and die" or "Go in and erase someone and die".
What if they nerf his damage? It's not all about damage, he is an assassin and he should be able to assassinate you quickly but if they nerf his damage, his kit simply won't work for him and he will lose his identity. Problem with Zed is his Passive that for whatever reason works against minions and unlimited range on the second part of his ultimate, nothing else but no, Riot will gut his damage because it's a lot easier to do instead of slightly changing his kit but leaving his identity intact. How can 
and 
have range scaling with ability level on their ultimates but Zed cannot? By adding some range on the second part of Zed's ultimate (ofc a lot shorter than Nocturnes, Pantheons and TF's) Zed's abiluty to switch back will be there but he could be punished for a bad play because well...if he ults that 
under his turret realizes he has made a mistake, by switching back to his R shadow he could be hit by Xerath and probably killed and punished...but why if I can let Xerath to push than press my R than he flashes, than I use my W and than I flash and jump across the whole mid lane under his turet, fail and than press R again and POOF I AM UNDER MY TURRET LAUGHING AT PANICKING XERATH!
passive proc with a single 1st AA...huh. The point is that you should kill her before she kills you which would be impossible if assassin doesn't have damage :)
