Tracking and Rewarding good Workfront Usage Within Our Dept.

We are trying to find a quantifiable way to reward WF users who keep their tasks up-to-date. 

But there are several challenges with this:

1. There is no real way to know from a report whose tasks are actually “up to date”. A person’s task could be “past due” but still accurate because that task is dependent upon someone else completing their task
2. A person’s task could be at 50% and not be “up-to-date”, while another’s could be at 25% and that task is completely “up-to-date”
3. There are several users who realistically never use WF, so they show as having “0” past-due tasks. It doesn't set a good precedent to reward those who almost never use WF over other regualr users.

Has anyone else been successful in solving a similar challenge?

Thank you.