League seems to be a bit more... "snowbally".
Back in, gawsh, when was that, Season 3?, Riot started to really hammer on champions for their tendency to snowball out of control (hello Riven, later Yasuo). It very much was THE buzz word back then. I tend to agree with this principle: just because you get that one lucky kill in lane where you escape with 10 health should not mean that for the rest of the game, you dominate the opponent without also executing well. There should be a reasonable expectation of crawling back into a game to win it in the end should you outplay your opponent. The margin of success should be smaller for opponents who are down, but at the same time, it should be possible.
That said, the game feels very "snowbally" recently. I think the biggest thing to point to is that with the new runes, they have a tendency to scale with your stats much better than masteries ever did. For instance, Tempo is a freaking late game monster, giving ADCs the ability to demolish anything in their path. I do think that the game benefits from the new runes, but I can't help but feel that snowball meta is returning, and something needs to be done to curb it.