The leaderboards at the moment are completely useless.
In my opinion the game needs two separate competitive mode, for solo players and for teams, where the leaderboards are based on the rank of the players in the relative competitive mode. In this way I think we can play more balanced matches, where players with similar MMR can be matched. At the moment is a little bit frustrating to be forced playing with low level players versus experienced team (I can't remember how many games I've played with me and three guys below level 10 versus 4 player over level 50 or worse 4 players grouped).
In addition, if you would like to learn a new carachter or do the daily quest sometimes is impossible because you have to choose if you want win the game or if you want do the quest.
If separate competitive modes are not created in a brief period, unfortunately I think that a lot of good players will be quit the game.