I don't know, I just leveled my NIN up, and on the offtimes of my server, too (some waits were an hour and a half for a dungeon...ugh).
What I'd do was... DR daily bonus. Guildhest roulette daily bonus. Hunting log. Challenge log. Queue for the two lastest-unlocked dungeon (slower than roulette but p much guaranteed half a level).

Took maybe bout a week and a half.