First of all I want to tell this: The highest elo I have played this season was D4, but at the moment I am recently training other champions, so I dropped to P2. I have climbed out of bronze 5 to where I am now. This happened in season 3.
The past few patches I have felt like Riot is not listening to the League of Legends community. These nerfs on (random) champions are not even the nerfs that we want to see. The real problematic champions are so obvious and still they will not be fixed.
For example: Katarina
This champion is mainly picked by people that are willing to pay no effort for a win/ are elo boosting someone/ just want to destroy other players by playing this amazingly OP champion. This champion works actually so well in low elo, but also in high elo. I actually picked this champion a few weeks ago a few times in ranked. I have never mained this champion. What happened? I turned out to be over 20 kills and less than 10 deaths in all the games. You can tell that people have no idea how to counter Katarina, but believe me, if the person mains Katarina, you are as good as done. I believe that the win rate on katarina is balanced (around 50% and not for example 60+%) because people are losing of 1. bad mechanics 2. bad behaviour(toxic) 3. Just bad luck(bad teams/toxic teams). I don't have a number but I would say that many people are suffering of these reasons.
Another few champions who are ridiculously overpowered close to being broken like katarina is) in overall ELO are: Irelia top, Leblanc Mid, Lee Sin Jungle(early game can destroy a team).
A few champions that work well in low ELO and are mainly used by elo boosters: Draven ADC, LEe sin Jungle, Riven top.
What do you guys think about this?