For human time spent, hunts would be the fastest way to farm gold. (Or literally buying gold, but will not go there.) Labyrinth:Look for little regions that stick out, go there for gold chests. Goal is to find them and push towards exit asap. Feel free to auto battle lab runs until...
You get 1 labyrinth entry token per day, plus one additional from the guild shop for a total of 8 per week, excluding any additional ones bought with skystones/leifs.This is enough to clear all 5 bosses if in at least 1 entry you manage to clear 2 bosses. A double boss clear can ...