I fines serve better as recompense for damages, not as punishments. I don’t see how a rich man speeding is a greater problem than a poor man.
So what are you going to do with people who break the speed limit? You’ve got to have sanctions, but jail sentences are a bit over the top unless they’re doing 80mph in a 30 mph zone. If you are a multimillionaire, a 50 dollar fine is like a small fee giving you a license to break the law. So any punishment needs to act as a deterrent, but not to the point where you are locking everyone up for a minor offence. What else would you suggest?