One of the best currency systems I have ever seen in any game is in Path of Exile, where the currencies double as usable items which you have to use often, thus are their own sinks to a huge extent. Though that game does have its own problems, botting and RMT is still ruining the economy there and GGG (the devs) can not fight it almost at all as it is a small company (something like 50-55 employees), they simply do not have the resources to fight it at all.
Also, on a related note, too many players here discussing Eve’s economy etc. are not even aware of the current business model and making wrong assumptions and jumping to wrong conclusions.
CCPs business model has shifted a few years ago, it is not to live off subs and / or plex etc. generated by wide player base at large. This is the wrong impression that most players have.
CCP is focusing on financial whales, multi account players with 10+ accounts. Their game design and ingame economy decisions also reflect this. Though when it started the income was something like 25% whales and 75% all others, that was a few years ago and has been steadily shifting towards the whale side since then. There is no data available as to where this number stands currently.
By default, everything that they do in the game that is good for multiboxers, such as keeping / adjusting combat sites to be done AFK, better multibox automatic logging in, ISBoxer support, etc. etc. is all also good for bots, hence we get more botting further pushing this and ruining game economy even more.
In addition, they are far less likely to perma ban accounts that have used both direct purchases from CCP as well as RMT, over those that are pure RMT, as well as the accounts that just “forget to turn of auto ISBoxer functions” on regular basis over those that flat out modify their game.
This was all done in order to pad sub / login numbers for short term gains. But it is hurting longterm really a lot.