Stricter Punishments for Flamers?

Hi,

My name is TiredOfLeague (ironic, I know) and I've been playing League off and on since ~late 2011/early 2012. I enjoy the game and usually have a good time with it. I never flame or give anyone a hard time - I make a point of keeping a level head - and usually people treat me in the same manner. However, I have had several games where I have played with extremely toxic, borderline abusive people which brings me to the point of this topic.

I report flamers whenever they're in my games. Recently I played a game with a Zed who, although he carried the team, was very abusive to everyone else and constantly flamed (i.e. "ur all trash", "sh*tty team", "you should go back to playing bots" that kind of thing for a good 35 minutes) when we did something wrong. I reported him and urged everyone else to do the same. As I understand it, players are only punished - via your report - if you get a notification. I have not received a notification for that zed even though his behavior would have easily earned a ban for a few days at the least.

Another, less recent, example is a Thresh game I played with a Draven jungle. I 'misplayed' (hooked lee sin to stop him from Q'ing and killing Draven) an engage at the beginning and Draven started flaming the crap out of me (typing in all caps, calling me stupid, telling me to kill myself, etc.). I muted and reported him after the game. To this day I don't know if he was banned, although judging by his incredibly mean behavior he certainly should have been.

What I want to know is, why weren't my reports sufficient to warrant a ban, or some other kind of disciplinary action for the previously mentioned players? I usually write 1-3 sentences outlining what the player(s) were doing to make my reports more specific. Do I need to write more? And if my reports are not sufficient, what is?

I mean I have been placed in 20 minute low priority queue half a dozen times due to (mostly) irl stuff that is beyond my control. Why isn't the same thing, or significantly worse, happening to people who go out of their way to be jerks? And where can I find confirmation that it is?

Thanks