Currently there's a problem with the amount of people trading items for real-life money, and NX for Meso.
The problem is that people are getting scammed and then not only having a bad game experience, but submitting tons of tickets to Support.
Solution?
Nexon could bring back the MTS (revised of course) so they can still have control, but players of all different types can get what they want-safely!
 
Some players have a lot of money or NX, but are unable to get the items or Meso they want.
Then there are some who have a lot of time/Meso/items, but no money to spend on NX.
Through the MTS, these players can get what they need by giving other players what they need as well.
If you need an item, you can buy it with NX. Then you can sell that item for Meso or keep it.
If you need NX, you can buy an item from the FM with Mesos and sell it on the MTS for NX.

Sure, it's not a perfect system-(obviously since it was removed)-but it's needed!
Why? Well, I think that, although it's not perfect, Nexon has to do something about just one of the many issues with their game. 
This can reduce support tickets, reduce the amount of players being scammed, reduce the use of websites that sell NX and in return reduce the amount of compromised accounts.
This feature can increase both the time players spend in-game and the amount of money generated from NX Cash sales.
How? If you knew that you could get the NX you desired by farming for an item/Meso, I would think many players would do just that. Also, if you knew you could buy items (which could then be sold for Meso) by using the NX you have, I think many players would do that as well.

This is my opinion on the subject and I really hope it gets heard!

One note: I would like for them to release a poll if and when they do decide to bring back the MTS that let's the players give their opinions on the revisions/features to be implemented. E.g., the tax bothered the heck out of me.)

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