Okay, Riot, seriously, let me help you out with Rengar and Kha'zix (x-post from GD)
Seriously guys.
You release two champions, rivals of each other, stalking predators who seek out weak prey and quite literally devour them before their prey know what hits them.
They are, in EVERY way, described as assassin-like characters. Predators do not "brawl". Predators do not "fight". Predators stalk. Predators wait. Predators take an opportunity, and kill. The end. Any Nat Geo documentary could tell you that.
These are two of my favorite champions in all the years I've played League of Legends. I know them intimately (bow chika).
I get the need, really, I do, to eliminate that no-counterplay 100-0 stuff (unless your name is Leblanc. Or Fizz. Or Talon. Or like 5 other champions. Then it's okay if you delete people), but you're going about this in such a wrong way. Or, if "wrong" is a "nope, not reading any more" buzz word for you guys, "you're not looking at this from all possible angles".
Firstly, I was all for the major nerfs that hit the both of them. Rengars removal of triple Q, and his subsequent rework. Kha'zix's crazy damage on Q, his outright gutting of evolved W. These were necessary nerfs.
What isn't necessary is doing/considering more Kha'zix nerfs every single freakin' patch until the game dies. Like seriously.
I'm glad to see you guys following up on Rengar, that's great. You're still trying to force him to be a fighter instead of an assassin (news flash, Lions, Tigers, and every other big cat are not fighters), which I really don't understand beyond "assassins are hard", but at least you're sorta trying to keep his assassin builds alive..ish.
However, you released Kha'zix as a multiple potential, INCREDIBLY unique, awesome, fun-to-play champion. And then you removed one of his evolution options from viability almost entirely without any compensation to it's evolution form besides (later) increasing the slow by 10% (hardly makes up for the like 50% damage nerf and the ability to fire in leap). And then just... lots and lots of damage nerfs (60% AD scaling off E? Really guys? >.>)
If you STILL think he needs nerfs, fine, okay, whatever, turn him into Shaco-tier I guess. But at least care about preserving your own character's identities, and your own character's designs, and your own character's lore.
Firstly, if necessary, dump on lane Kha and lane Rengar. Yes, they're good, and they're fun, but that's NOT WHERE THEY SHOULD BE. Seriously, NOTHING about these two characters implies laning is where they'd be. They're junglers. As long as you guys try to make them equally good at both, they're going to be problem champions. They don't have to suck at laning, but they should be better, unquestionably, at jungling.
Second, if you're going to nerf Kha (again), make evolving his W just as viable as his other abilities. Sooooo much potential for an awesome champion that you guys are wasting by forcing him into ignoring one of his evolutions. I still say making his W his strongest potential slow (items included) and clustering the spikes closer would go a long way. To be honest, E will always probably get evolved. That doesn't mean nerf it, that means make the other options as enticing.
Third, make Rengar able to duel if he must, but the primary part of his power be in his up front burst. Right now, it's almost opposite. I don't want instagib Rengar back in ANY form, but he's not Darius. In fact, he should be playing the opposite. Up front damage and then tapers off the longer the fight goes.
I mean, c'mon. If you wanna make new champs like these guys and make them laning fighter-like characters, go for it, I'd bet they'd be awesome champions.
But don't take the only TRUE predator characters we have and make them in no way play like predators. Don't make such an awesome character in the form of Kha'zix's evolution concept and then make one of his evolutions pointless and then start nerfing the rest until they're equally pointless. Don't make Rengar into a wanna-be Tiger Stance Udyr who's better at 1v1 fistfights than pouncing.
Hell, hire me on, I'd love to help out with these guys. I'm not saying "OMG NEED BUFFS", they obviously don't (well Rengar maybe, but I'm of the mind it's more of a power-allocation issue than lack-of-power issue). I'm just saying the way you're handling the nerfs isn't fixing the issue, but it is killing the characters and their fantasy.