At this state group finder is a joke, forget about bugs it just need to be much more smart to match players in groups. You're loosing a hell lot of players because of missing matchmaking. Look at WoW/Overwatch, they've implemented a wonderful system that uses a lot of player statistics to match player, why not bring a similar system in this game?
I'm playing occasionally since 2014, I'm not an elite/pro player, I've never completed vMA or any veteran trial, or any veteran hist dungeon. But I have some kind of playing style you must know, because you've been collecting player stats since 2014 (I hope so...) And I'm sure a lot of players play like me and I would be very happy to play random dungeon with them. But I just can't because there is no way to connect us together.
And duels... They are absolutely behind the bars for me because I'm not a PvP person and a few time I tried duels I failed miserably. Why not make duel matchmaking that connects player with similar stats (not skill/resource stats but ”historical” stats of account, playing style etc)?
You have such great potential but loosing it because of missing smart matchmaking system.