I have seen this rank on another server. What it did was the non donors take a test/quiz and get teleported to the next question if they get the answer correct. This would be a test on the commands of the server, the rules and on things like that. At the end they answer one final question and receive a prefix (only a prefix) that shows that they have done the test, they know the rules and so on.

This suggestion, modified, could be an incentive for the majority (non donors) to learn about the server they have joined, as well as show other players who they can trust "more". But it also allows a fun way to get the rules across to the players.

While I know it is very unlikely this suggestion will be taken into consideration given Cyp already saying no more ranks and Crew being fine with the ranks there are now, possibly if the need is there then it will.