Ranked progression.
I think the biggest problem with ranked, is that it's not dynamic at all. Players SHOULD NOT be floating around the same rank over a long period of time.
Players on losing streaks should be bumped down to Bronze 5 . . way faster, loses should be loses and wins should really feel like wins. There more to lose when you lose ex; points, demotion, loss of promo is also loss of points. Winning? You end up with 99lp, your promo has trolls, you go to bronze4-1,s4-1, then you have to win a best of 5....
Someone could also argue, losing games doesn't cause much of an effect on rank either (I'm looking at the Silver 5, Gold 5, etc 5 ranks that are deranking or simply "don't care" anymore players.
I really think MMR should be added to the game, so what if you're the lowest MMR of 5? You'll have to put out a bit more rather than have that ADC that "doesn't care anymore" because they're behind and starts spamming /ff
It's just ridiculous to me how SLOW ranked is. Progression is too slow, want a comparison? Look at CSGO. Match lengths are literally the same duration as league matches.
Solution? Show MMR Points gained and lost should be doubled Promo's need to be removed
And if a player is on a lose streak, they'll prob just end up quitting anyways at bronze 5. Then the more serious and dedicated players (THE ONES YOU WANT) that try hard to win, stay in the "serious" game mode.