Temporary Game Mode: Realistic (Hardcore)
I think it would be a great idea to have a temporary Hardcore game mode for PvE only. In this mode, if a player is to die they will never re-spawn. While the bots continue to come back time and time again. If all Human players are dead, then the game is an automatic Defeat.
The point of this mode would be to teach better teamwork and better decision making. This also reinforces people to party Queue instead of just solo Queuing all the time.