I've been solo'ing ARR dungeons/trials in my downtime with Undersized Party. I'm curious as to whether or not anyone else is attempting this and what success/fails they've had. Below is a list of what I've completed as 60 DRK:

Dungeons (completed)
Amdapor Keep
Aurum Vale
Haukke (and everything below)

Trials
Garuda (Story Mode - Complete)
Titan (Story Mode - I can get the heart down, but not before Gaol which is instant reset)
Ifrit (Story Mode - Complete)
Cape Westwind (Not complete, but am getting closer to victory)