Exponentially scaling property taxes and especially moving violation fines for heavier vehicles seems like a great way to align incentives. The heavier the vehicle, the more-strongly you're encouraged to drive safely (which makes sense, as heavier vehicles are more dangerous); if you have multiple vehicles, it encourages you to use lighter ones unless you really need a heavy one for a given trip; and they'd remain a viable option for safe drivers who really need one (but even those drivers would be encouraged to get the smallest one that'll get the job done).