AFK's in Ranked Matches

After multiple games in ranked I get sick and tired of getting AFK's or disconnected players. I understand that sometimes it may not be their own fault, but something should be done to equal out the fact that one team is down a player. If a system in place were to cancel out all LP lose and gain from said match with an AFK or disconnected player, that would make more sense. A 4v5 match is only fun for the full team. They get to roll over the enemy team without a care in the world and will almost always win their game. Say after 5-7 minutes of a player being disconnected it would cancel out all LP gain and loss. Then if the player reconnected at all during the game, LP gain and loss would become a factor yet again. I'm tired of losing LP because the player is unable to disconnect in the first place. I would much rather have a 5th person that doesn't play the game that well over an AFK. It adds a highly unfair advantage to one team. I fell this should definitely be looked into.