On the general topic of the recent PBE changes to Kha'Zix, I want to express my opinions and observations. First of all, I feel like the buffs to his ult are much needed. I main Kha'Zix and I hardly ever find his ult to be very helpful, especially because of unit collision, which is now removed. The movement speed buff is great too. However, the damage nerf to his Q and E I feel is too much. I just played a game as Kha'Zix mid vs Gragas and my Q would do hardly any damage to him, **even if he was isolated.** This prevented me from doing even relatively well in trades and left me behind in lane. I honestly think that the nerf was rather unnecessary. His Q is his main damage ability and now does hardly any damage without heavy itemization towards AD. I'm not sure what the context was behind the nerf to his Q, but from my observations, it seems to be too much.
EDIT: Jungle Kha'Zix is near impossible. It takes way too long to kill jungle camps and he loses way too much health during that time. Literally the only reasonable way to play him in the jungle is to max W as much as possible and gank lanes constantly, which now has less impact due to his Q and E being nerfed. Jungle Kha'Zix is such a terrible idea now..
EDIT: New changes coming to the PBE for this guy. Q dmg has been changed to about the same as live at early ranks, but slightly lower than live at max rank. Evolved ult back to 50% dmg reduction from 60%. Evolved ult now **DOUBLES** the movement speed buff from his ult..this means that he will gain an 80% movement speed buff when using his evolved ult. Also, the AD ratio on his E has been restored to live values.