I don't think reducing prison time would necessarily result in all of those. Closing jails perhaps, but it's possible such a thing would require more police and county court bandwidth, not fewer.

That said, I believe non-violent offenders should never be put in jail. Give them mountains of community service or some other more productive remedy. If it's financial crime, freeze their ability to access the financial system. But sending them to jail is more likely to make them more effective and more hardened criminals.