In game voice chat
Throughout the couple of years I have been playing League I continuously find myself in games where as soon as a team member die's it begins arguments that build up right until the game is lost. This starts because players in the other lanes can't understand what occurred in the 1v1 (or gank) and therefor feel the players death was needless and become angered or 'salty' by it.
When playing with friends in a voice service such as Skype this typical situation in almost every game happens a lot less as there is communication. This is why I thought the idea of Riot introducing a separate Que using the same up-to-date patches but with an in game voice channel such as the ones in games like Over watch and CsGo. This Que would still count towards the same leader boards as the existing Dynamic que.
I'm very sure there would be many complications In actually putting this idea to work but I also know that there is a huge percentage of the LoL fan base that don't know others in person that will play league with them and would enjoy the use of communication with 'randomers'.