One thing people seem to be missing is the massive nerf that SE applied to the price of reselling items to NPCs. When ARR was launched, everyone's gil was cut to 10% of their sum total (i.e. if you had 1,000,000Gil you started ARR with 100,000Gil). I hear you already: "But SE cut the costs of everything to 10% so it's all relative and your point is moot" well, yes, but no at the same time.

With the revamp of items, and costs of items, and the resale to NPC price of items, they have nerfed a lot of what was viable to sell to NPC for gil. For example, the incredibly easy and common marmot skins used to NPC for something near 400gil - It was possible to pull in about up to about 10 stacks an hour just smashing these level 1 furries (10 x 99 x 400 = 396,000 gil). So you would think that the 10% rule of ARR = 39,600Gil? Nope... they nerfed the resale price of animal skins to 1Gil - which is now 400gil per hour.

My figures may be slightly off, as I am going from memory, but I remember it used to be a nice, easy and steady source of income - especially for lower levels. There were lots of these kinds of easy to farm, common drop items - Silver ore and obsidian used to drop like mad from the Spriggans, but no more.

Maybe there are efficient ways to generate gil into the economy which haven't been found yet, I don't know. What I do know is that they have nerfed a lot of the old methods.