So I know that players get temp banned for leaving a game in progress - and maybe that increases the more times you leave, dunno. Anyway, the problem still exists that 3v4 and especially 2v4 are very difficult for the uneven team to win. Since wins are the only thing that seems to count towards raising/lowering CSR seems a bit unfair that a crappy situation like that will negatively affect your stats.
What should be done about asymmetrical teams in Arena?
My suggestions:
If 1 player leaves, then if the team with 3 people wins they get a 1.5X CSR multiplier to a win. If the 4 team win then they would only receive only 1/2 the normal CSR boost for a win against the unevenly matched opponents.
In a 2v4 situation I think that the game should just be a rematch. Playing out a 2v4 is pretty awful, I’d rather it just send me back to the lobby.