I've encountered a few instances where the Tank leaves from he start anytime I got paired up with a MNK on DF and its rather infuriating.

Yeah they have to wait 15min before que up again but DPS have to wait 30+mins for another hit on DF and I don't think these odds are fair at all. Honestly Tanks, if you don't like getting paired up like this then don't use DF for speed runs and form your own group.

There needs to be a huge penalty for leaving a group early into a Dungeon. Like within the first 15mins if someone leaves, they have to wait an hour before they can run another dungeon.

And I know there's going to be a ranking system put in place, I hope you will be able to rate people negatively for ditching.