It's been about a year now since the big revamp of the Galactic Trade Network, and I wanted to use the occasion to post some thoughts on how things have been going. Overall, the deflation of the economy due to the taxation changes has been absolutely bananas (which, to be clear, is a good thing), and the GTN has probably played at least a part in this.
Transaction fees aside, the sales data it provides makes it obvious to potential buyers what other players have been willing to pay for an item in the past, so it's much harder to artificially drive up the price of things, and you can't hope to just fool someone into overpaying by making sure that you're the only one selling and putting a unreasonably high price tag on the item.
The only annoying thing about this is that you can't see this sales data if there isn't already an active listing, and the prices that the GTN "recommends" based on this sales data don't always make sense, in either direction. I saw this recently when opening some of the Cartel packs you get from the Galactic Seasons track on the Shae Vizla server, where the GTN is a lot more quiet.
First I got what I thought was a new-ish and pretty rare weapon which had no listings on the GTN. The system suggested I list it at 30 million credits and I was like "sure, that sounds reasonable for a rare weapon". Then I opened the listing I'd created and...
The historic price was less than half a million? Why in the world would you recommend that I try selling at 30 million then?! Needless to say that listing expired and I re-listed it at a lot less afterwards.
However, it works the other way round as well. Another Cartel Pack gifted me a bronze armour set that wasn't currently being sold on the GTN either. I know that those usually aren't worth that much, so I wasn't surprised that the recommended listing price was only 10k credits. But again, I checked the listing afterwards...
... and the historic range was ten times as much. Why do you do this to me, GTN? I'd really love to know where those numbers come from.
Also, whatever happened to those buy orders we were supposed to get with the new GTN? I was really excited about those but haven't heard anything about that feature in forever. I thought being able to add new functionality like that was partially the point of revamping the whole thing in the first place.