I was playing a few rounds with friends when we had an AFK in a really balanced game that them became quite one sided. We had an idea that someone from the solo queue could jump in and fill in but doesn't lose rank if the team loses and would gain rank points if the team wins. Usually the afk would be on a losing team so of course no one would jump in to a losing team but if we can award substituting players if the team wins but not penalise them if they lose it might make matches be more of a better experience for those already in if there is an afk on any team. Of course this should be limited to reduce people only playing as subs to farm rank ups but would be a neat idea to implement.