This game is designed so you can't farm any one thing.

It operates on the idea that you farm everything and then sell the sfuff you don't need and buy the stuff you do.

Unfortunately, it only partially works that way.

As, so often, the thing you need wil be overpriced and/or will have sold out by the time you find a guild store selling it and have travelled to the trader to buy it.

This is because the stuff you need is, too often, the stuff everyone else needs too and also, because (with the unlimited craft bag) people often end up hoarding mats for later (just in case they need them) and don't sell them very often.

Really, there needs to be two ways of buying things - one for mats and then another one for crafted items, blueprints, motifs, furniture and gear and so on.

The guild store system is a good idea, for the latter, as it makes it harder for people to instant undercut, by 1g and so on.

Which is the issue that auction house only selling systems always have.

However, it is a horrible idea for mats, as they generally sell far quicker and no one wants to traipse around the world, for hours, trying to find some reasonably priced rice...

So, you really need either a mat-only auction house, or a mat-only warehouse, which sells all the mats in one place; while retaining the guild store system (or some other individual store system) for everything else.