One of the greatest things about EVE ONLINE is the in game economy. There are countless great news stories about how expensive ships are in EVE and how much wars cost in ship destruction. Many players come to EVE for the economy - the buying selling and crafting is very robust and fun.
However with the change in PLEX and ISK and subscription based model - EVE has seen a lot of people stop playing.
I propose that EVE implements a cryptocurrency similar to Bitcoin that will be used as in game currency. You could give long term players larger amounts of this currency and switch things over.
There are many gaming tokens launching such as WAX, EBOOST, UNIKOIN. etc. But most of these are game specific or have different uses. An in-game currency that was decentralized and economically stable (and goes up in value) and earn players real money in the form of a EVE Token - this would be awesome.
Please do not neglect the in game economy as it is one of the main reasons people play EVE.