Coming from who you? I've attained Diamond in both games. I quit League not because of imbalance though, because the community is garbage and the Dynamic Q system is extremely worse than Overwatch in terms of FPS is a more friendly Dynamic Q system than MOBAS.
The game literally has a quarter of the toxicity that I've seen in League.
I've played League for 4 years, I used to average 5-6 games a day. I now play for an amateur Overwatch team and maybe play 3 games per 6 months in League.
Also, it's not just me saying this, all my friends have moved on from League and play other games. Not even that but every single website in the world would rank League as the most toxic video game in the history of gaming.