I'm new to this game. I can't tell you about anything higher than level 55. Here's what's annoying me now. Some dungeons are harder than others. I'm starting to think that tanks are intentionally undergearing and trolling the hard ones. I can't guess why they'd do it, but I've been in two today where the tank in a level 35+ dungeon was wearing level 20 gear. My suggested remedy: To qualify for a dungeon match, your gear level should be good enough for it, not your class/job level. It would at least force the trolls to make a gear set to annoy people with. It would be even better if, once you are in a dungeon, nobody can change gear. At least for the roulettes. It's foolish to spend 90 minutes on a roulette because some guy thinks it funny to keep losing aggro and getting the healer and mage killed.

OTOH Most of the game has been surprisingly well thought out and free of trolls. This is the exception, not the rule.