This new ranked system is not going to be a good fix for ranked gameplay.
https://nexus.leagueoflegends.com/en-us/2018/04/dev-updates-to-ranked-for-2019/
And it seems Riot realizes this because they had to address these issues.
"Master and Challenger are a little bit trickier. Those players don’t get their primary position as often, and it’s important for the integrity of the ladder that every game they play counts toward deciding whether they’re the best."
and
"One more thing: we know competitive intent is a big deal in Ranked, so we’ll be rolling out new systems to help combat situations where players don’t take games in off-positions seriously."
don't forget
"We’re solving a number of other edge cases like these, including position swapping in champion select or in game, and we’ll talk more about our solutions for those in future updates."
I'm a Master tier player. It took me almost 300 games to get there. At least a couple dozen of these games I was autofilled.
100% of my games were in Plat/Diamond as I haven't played yet on my main since reaching Master. I say this because if it was implemented this season, it would've affected 100% of my games. I'm speaking from the perspective of "how would this system have affected my climb?" Bear in mind the new system isn't fully fleshed out, and we don't know everything, but this is how I'm thinking it works and the possible flaws in it.
I don't want those games where I'm autofilled to slow me down from grinding up elo, as I am capable of functioning in 3 1/2 roles (the jury's still out on top lane). I don't want my queues slowed down because the guy who WAS gonna be the autofill on my team to finish up the queue is now playing with a bunch of Gold players. I don't want to drop 2 divisions and grind out games on a separate part of the ladder every time I play my secondary, ADC. And I certainly don't want to play with players who have significantly less game sense just because I'm not familiar with pathing and I got autofilled jungle. I could just as easily role swap or dodge.
And keep in mind, as you get higher elo your chances of getting autofilled are much higher. This means that climbing is effectively going to pile on autofill games that I and other people really don't want to play since we enjoy playing with teammates with more game sense. I have almost entirely stopped playing normal games and match quality is the big reason why. Low elos will often change their strategy from playing the game out normally to 1v3 camp the high elo guy and in a role I'm not super comfortable in, that's not enjoyable. This will bring that feeling to games I already don't want to play because I got filled into Gold elo ranked jungle.
Lastly, Riot says they want to deal with competitive intent, but it's very hard to punish people for int. feeding because it can easily be explained over as them having lapses in judgment. I know this because I have lapses in judgment where I do something really stupid and die freely from it. I joke that I'm inting when that happens because essentially, I did int. I didn't mean to get myself killed, and I certainly shouldn't be punished by ranked restricts, bans, etc., but dying was the only reasonable outcome that would've happened if I stepped up w/o my support, or went through the river instead of around it.
tl;dr outside of Master and Challenger the ranked system sucks because it punishes high elo non-Master players who actually want to climb and grind up to Master by making their climb slower w/ autofill games, and i don't actually believe they can punish competitive intent nearly as much as they insist they can.
I can see that being really frustrating, say you main mid and you are on a nice win streak and all of a sudden it auto fills you to supp, what makes you want to win that game? If you don't give a shit about your supp rank then 4 other people are gonna pay, cause all you care about is your main role rank.
To elaborate on my point, I'm going to play the game out because I don't like playing the role of elo terrorist, but I dislike playing with players who are significantly less knowledgeable about the game than I am (makes for much more frustrating matches on my end), and if the enemy op.ggs me my poor ADC is going to get camped because the enemy will be like, "We have to shut down the D2/D1 guy." Even though I'm, mechanics-wise, on the same level as every other player there.
