Instead of auto-filling
Do you think Riot will ever implement a system where we can choose a tertiary role instead of autofilling? This has the potential to decrease queue times while also allowing players to still have some control over what role they play when it reaches the point where the system wants to autofill them. That way players are less likely to be put in a role they have little understanding of, which could ruin the game for them as well as the people they are playing with.