How to Fix ranked
Remove flex queue, rename Normal Draft -------> Draft pick. Give everyone in Draft pick a rank, that only they can see, and let them decide if it is important to them. Don't give boarders in Draft mode, and keep it so you can play with anyone.
Keep solo/duo for the tryhard solo players.
It isn't like Draft pick doesn't already have a hidden MMR, it would be easy to implement, it would give self worth to those that want a rank, and it keeps less queue's with the same game mode available.
FOOD FOR THOUGHT The Most important part of this is having everyone's rank be secret to only them, or even better don't even reveal it, just give out rewards at the end of season if they make it to "gold or higher". If people want to 5 man Draft with a challenger and three bronze who cares...