One word, Elytra. Voting already grants wealth just takes a long time. If 75 votes gives a total of 40-ish diamonds blocks you can work out you get 5 diamonds per vote, so when you say that voting doesn't give people wealth I don't know what the hell your talking about. Now, you talk about the weakening of the price of emeralds and diamonds, cause at the moment they are the main currency people like to trade in, however... If you decided to replace the emeralds and diamonds you are just going to make crafty coins decrease in price, depending on what currency is predominant, Decreasing the price of it could result in the vote giving less money which was another concern of yours. While diamonds would retain a healthy price because you wouldn't be swapping them.