Regarding sales tax vs. gas/diesel tax to fund roads. I have not had the time to research the surrounding states current fuel tax rate, but I do remember a situation back in the '60s where Missouri raised the rate which elevated Missouri above the surrounding states.
What happened, the truckers who watch expenses closely and can travel a long distance just started filling up in surrounding states. How do I know this I had a relative who's service station suffered greatly. I really feel a mix of both fuel tax and sales tax would be the best approach.