What we need to do is to let people to rank up normally after receiving at least 100 merits and never let them to send any merits to others. when you have the ability to send merits and rank up other members, you'd go with your nature to rank up your alts.

Monitoring 80 or 100 people is easier than monitoring thousands. now if you already have received 100 merits, you should rank up with no merit requirement and you shouldn't have the ability to send or receive any merits.

EDIT: disclaimer: the tongue of my language is not my English mother.