I don't know if income would be a sorting dimension here. Account history and delinquency maybe... But if the service is say $40/month from an operations or BI

I don't know if income would be a sorting dimension here. Account history and delinquency maybe... But if the service is say $40/month from an operations or BI perspective, what advantage do you gain by prioritizing wealthier customers? A far better solution would be to have a 900 number for the wealthier customers to call where you charge them a premium for faster service. They'll self sort and you don't have to do anything.