Auto-matchmaking for abyssal dungeons could use a slight tweak regarding team compositions.
Example A: a team with support Bard + 3 Blades is going to have a hard time passing any boss with wipe inducing stagger checks (especially in lower tier where a lot of people are still learning to master their classes/battle items).
Example B: a team with 2 bards and 2 paladins might suffer from lack of dps, leading to boss enrages.
Yes, in example A one could compensate the lack of “stagger skills” with the use of whirlwind grenades but I doubt that’s common T1 knowledge (no offense, I could be totally wrong).
A simple class limit/team could help frustrating situations for newbies.