Don't punish the ones who get stuck with people who leave
Can you make it as the team who loses players in ranked not lose as many points considering it's not their fault people leave. Last 5 rounds I have played someone has left every game leaving our team 4 against 5 from the start of the game or very early. Maybe if the team loses a teammate cut the losses in half. So if you would originally lose 18 points maybe make it 9.