Ever since Teambuilder and Ranked 5's were removed, there are only a total of 3 queues instead of 5 for people to play for 5v5, and there is only one ranked mode. That means there will be more people in each of the three queues than ever before.
I don't think Riot's argument that two roles are necessary to maintain shorter queue times really holds up when they've removed 2 entire queues from the game. There should be more than enough people queuing up for every role in both of the dynamic queues. I bet even mid mains would not have to wait more than a few minutes for a game at most elos.
I mean even when I used to play teambuilder and queue up as mid at some odd time like 2 in the morning I never waited more than 10-15 min for a game.
Let us queue for one role please.
EDIT: It's getting really old not being able to play mid ever, and if there's really that much of a shortage of supports all they would have to do is incentivize queing up for support with some small IP bonus