The biggest cause of the lack of grouping now, in my estimation, is the Update 12 class revamps. The classes just don't work together as well as they used to. The balance was thrown out of whack, and it has become more difficult to ameliorate. It takes months for the developers to introduce adjustments to class skills, and these adjustments usually overcompensate, requiring a further adjustment months in the future. The OODA loop wasn't functionally shortened.
Group content has become less fun. The game needs another class revamp to restore the classes' lost utility.
I do not love the bright sword for its sharpness, nor the arrow for its swiftness, nor the warrior for his glory. I love only that which they defend. ~ Faramir
Undo the U12 class changes. The trait trees were, are, and will always be a bad idea.
Maedhric 100 Captain, Nunion 93 Champion, Taraviel 85 Minstrel, etc...