I am afraid that you must just not face good ones. Zed is without a doubt the best midlaner right now (in the right hands of course). Its tough to do winrates on champs like that because everyone wants to jump on the band wagon for "freelo." There is a point where this wont matter and people can just faceroll for the win, but I agree that zed is not at that point. He is , however, strong at every point in the game. Maybe he is a little weak pre six, but there truly is no stopping him after that unless he loses lane Hard.
As for Lee, he is also getting nerfed constantly, but still considered top teir jungle. His mobility is really impossible to deal with since wards are so readily available. He can just do everything and do it well. His only weakness is his late game, but even then he is still a huge play maker.
The biggest problem I see with these two and others you mentioned is their contribution to mobility creep. With mages like Veigar being nerfed and Annie on the cutting board next, there truly is no reason to pick a non mobile champ. Riot has stated they want more reflex based counter play over strategy, which could eventually be good. But they are in the transition and doing it very poorly. They are cutting down champs that could handle the mobile ones right now rather than reworking them. This is honestly just creating more problems that will have to be dealt with later, but they can be covered up for the time being. I think this is the reason why people do outcry about champs like the current ahri (very balanced) and LeBlanc (kinda balanced).
For veigar,I personally would have thought the q change was fine if they compensated the W a bit and brought his E in line by reducing the stun duration. Veigar was honestly quite balanced before, but had a toxic ability. So if they moved things around, he would be in a great place. However, they added weaknesses and removed strengths. They also removed a champion that could deal with mobility creep. Hence why people are even more upset.