So, lets have a discussion :).
Bans and unjust punishments can and will be undone despite the "no punishment will be reversed." What that refers to are punishments given out correctly. Simple to misunderstand that. Perhaps an example would be a sign saying "No animals." but they still allow service animals in.
Off meta can work at times, even that Teemo jungle. If it is played effectively then it can be quite oppressive. This remains true for other lanes/champs too. Yes, I may prefer a different jungle but I also rather them not "first time" a jungle they don't know.
You seem to want manual reviews, so a tribunal sort of deal. Sure we can get a review by one person but for best results you want probably 3 different people to review a case (in case someone is tired/having a bad day). These judges would need to watch entire games and even if someone was premade (enemy reports because someone built 6 warmogs on a Mundo. But mundos team was premade and okay with that build.). We will go with 30 minute games on average. A work day is usually 8 hours. So a single worker should check 16 games/cases in a work day.
They could hire 100 people for this and boom 1600 cases/game reviewed a day. That is nice and all but does it make even a dent? I'm going to throw out some low ball or high ball numbers. Low ball: 1 million people play in a single day. 10 people in a match so 100k games played.
High ball number: in 50% (basing off my experience and estimation based of forum complaint) of those games someone is accusing another player of trolling or intentionally feeding. So at least 1 person gets reported. So now 50k games need to be reviewed.
Remember our previous number? 1600. They can just hire more people.
Maybe but remember more than 1 million people play everyday. We also didn't factor in reports for verbal toxicity. And the 1600 number is also basing off only 1 person reviewing a case; if you factor in the 3 per case the number checked is less than 600 per day, about 533. Even a mutilmillion dollar company would be hardpressed for the amount of staff needed.