Forgiveness system for ranked play with AFK teammates

As much as I appreciate the remake system riot has put in place, it has no effect on people who disconnect or leave the game later on. I'm not saying a remake at any point in the game but I would like to suggest that if I have an afk that has left the game for atleast 5 minutes from the end of the game, that if the team with the afk lost. They should take less lp penalties. The time may need tweaking but I feel like it gives a good breadth to prevent abuse of the factor. Such as having a teammate afk just before the game ends to take less LP loss. Maybe this specific idea won't work but I'd also like to hear other suggestions on how riot could help the teams that afk or disconnected members later into the match.

Tl:Dr: What should riot do to help teams that get an afk later in the match