Sorry, but no they wouldn't. They might make YOU feel better, but it would do VERY little to solve the problem. In fact, I'd bet a fair amount of money that you'd end up with deadlier vehicle vs pedestrian accidents because you'd dramatically increase the number of hit-and-runs, reducing the number of pedestrians that receive prompt care.

The consequences are already quite severe, though subject to some uncertainty and heavily based on the circumstances of the accident which... is probably pretty appropriate. In basically every other context in criminal policy, increasing penalties beyond a certain point really doesn't affect the underlying rate of the target crime by very much, and can actually be harmful. Three strikes laws are a good example where a run-of-the-mill crime gets turned into a situation where you might as well go for broke and murder every policeman you see because you're going to prison for life anyway so criminals are incentivized to do whatever they can do to escape.