I agree, a whole lot of people crying and whining. Also, I don't feel like the sustain form that keystone is as huge and game changing as people are making it out to be. Of all the people that get the benefit of it fast, Pantheon is the one that gets it fastest with his last hits. People think it is every crit as well, there is a cooldown and I feel Panth uses it the best cause of those last hits. Yasuo takes time to get to the point of critting, and even then his crits are reduced damage so his sustain is also reduced (and it is already pretty low to begin with, 15% is a pretty low amount of healing for a crit on a cooldown).
I am liking the fact the people don't know how to deal with champions anymore, you have no idea how much damage an unpopular champion is going to do yet. The chaos is nice because it means the champion pool of viability will expand. I feel as though some of these keystones will make different team comps more viable than before. For example, Deathfire touch is going to bring back more pokey ap mids rather than league of insta-bursters. And obviously there is a lot more.
Mainly, I feel like people are in an overly whiney mood because what they thought was how the game played is now being changed. Riot is forcing meta changes and enhancing different playstyles. They also don't want 45 minute games and people seem to hate that (I personally am ok with it since gold gen has also increased). It seems the majority of players posting on the boards were static in their ways and want it to always be like that. The game has to change or else it will get old and get shelved. Good for Riot for making such large changes and trying to relay to the people where they want to go with it, even through this seemingly large ocean of salty comments.