Unfortunately, I can't help on your original question.
One helpful suggestion, however, is that you should use the award tickets for the people who are *infrequent* flyers and the paid tickets for the people who fly a lot (e.g. yourself). you can count the earned miles toward status and you will avoid having them be "orphaned".
This is how we manage it in our family. Of course, I always vote myself the tickets that are bought with money.