So, about the ranked system...
Placements, and the current ranked system in general, is absolute BS.
There are people in Plat 2 S5 getting placed Plat 4. There are people in Plat 3 S5 getting placed in Silver 3. Why such a big gap? Re-doing placements/ranked anxiety shouldn't be THAT big of a downfall...
On top of that, players new to ranked get royally shafted, often placing silver to bronze when they play nothing like a silver or bronze player. It's nearly impossible for a first time person in ranked to get placed in Gold, let alone Plat.
Yes, I understand most of League's playerbase is bad. and I mean BAAAAAD. I've seen some shit and it's god awful. But the ranked system is totally 100% flawed.
Going up/down by upwards of 200MMR (2 divisions) in placements inflates/deflates your skill, and especially if you play League how MOBAs SHOULD be played, as a TEAM, you get royally shafted by this system.
Starting at a flat (hidden) Silver 3 rank then going up/down from there is also pretty flawed. Your normal MMR shouldn't exist until 30, imo (levels in a MOBA shouldnt exist in general, but not the point right now), and your normal MMR should effect your starting ranked MMR, to an extent.
Supports also get 100% buttfucked until you hit about Plat, unless you're playing a "support". (looking at you, Annie) It's total bullshit and makes people who enjoy and are good at supporting not enjoy the game as much. Plus the whole community issue of "OMG I DIED REPORT MY SUPPORT" thing.
The community is another issue with ranked. The community is basically CoD without mics, AKA 10 year olds screaming at you for doing a tiny thing they didn't like. And no, none of you are capable of defending this and you know it. This is the community. Yes, a lot of online gaming communities have gone down hill (oh, the good old days of playing RuneScape in 2005... People were genuinely nice, for the most part...) but League's is by far one of the worst. This needs fixed, and part of it is just that people are obnoxiously rude and hateful nowadays because they can and want to. I understand that Riot is doing what they can, and I KNOW they are, I've gotten numerous "a player you've reported has had action taken against them!" messages. One day, I played 3 games, all 3 games I reported someone and got that message shortly after. The people were so awful, I tilted and stopped played. I rarely tilt.
The last major issue with ranked is the AFK system, or lack thereof. AFKs are not handled at all, they just exist and you get fucked by them. Part of it is community, part of it is the people not realizing "Hey, I have shit ping rn, maybe I SHOULDN'T play ranked...", and part of it is the servers. All 3 work in perfect harmony to create AFKs and DCs that don't get solved at all. Player's dont get a redo, the games don't get nulled, there's no In Game changes, nothing. It just happens and royally fucks you over. Look @ DotA for an example of how to deal with AFKs/DCs properly...