Maybe we should go back to the wealth requirements common when the Constitution was ratified.  Voting was limited in many States to those who had sufficient wealth to have some 'skin in the game' to use a modern phrase.  "At the time of ratification of the Constitution in the late 18th century, most states had property qualifications which restricted the franchise; the exact amount varied by state, but by some estimates, more than half of white men were disenfranchised."