Since most new cars have some form of GPS tracking system. Maybe a more fair / accurate method of taxation to pay for road improvements would be to track number of miles driven per car in any particular township and tax per mile. businesses would count the mileage between the office and their employees residence and pay 2x that as well (for to and from work travel). The result would cause the people / businesses that use the government supplied roads the most to pay the most. Discounts for using public transit. Imagine how businesses would back public transit if they get discounts for usage.
The problem with this system, if used for other government provided services, is that many services are for the betterment of everyone. For example education. Everyone is better off is everyone is educated. The smarter everyone is the more advancements will happen. Maybe even fewer people in jail. The bar for society as a whole is raised. So, Everyone should pay equally to educate everyones children.
But it might work for the roads. Maybe.