Short prison sentences should be replaced with either longer sentences or community service.
Why does this idea matter?
Short sentences don't help anyone, people in prison for short periods don't learn anything and it isn't a deterrence for some people.
People for who short sentences do present a deterrence, would be just as deterred by high visibility community service. For others they need to be locked up for long enough to receive training and rehabilitation so that they know how to do more than just commit crimes when they get out.