Between so-called "toxicity" and dynamic queue, I'll take the former
New champ select will clear up a lot of toxicity that existed in the old soloq. In addition, I can simply hit the mute button and easily ignore people. If players continually break the rules then they will get punished. It's like Riot doesn't even have faith in their own punishment system. Give us back soloq. Dynamic queue fucks everything up because of the randomness of premades and the wide range of mmr that exists in ranked games.