Prepare for Counterattack - Also known as prepare to afk for 10 minutes since the mission takes forever.
Spider Overload - This was just boring, and getting swarmed by spiders as a Sword Fiona who can't DPS them all wasn't much fun.
Hunter at the Ruins - This boss was always exceedingly boring for me, even more then most other archer bosses.
Hidden - Great grinding spot, yes. But I feel this is a reason why a lot of 61+ players can't play their character properly.
Nightmare at the Ruins - I'm just tired of it from how much AP grinding I did.
Weeping Queen - Never any parties for me to practice with, so I hate how she's the one high level raid I'm unfamiliar with.
Those are the main ones.