perhaps I’m missing something, but if you’re looking for an alternative, why not abandon the money aspect entirely?
It seems that posting money is being used as a surrogate for concerns such as flight risk, likelihood to re-offend, and so on. Why not give the judge the power to assess the application for release on those grounds? If the flight risk/danger to the community seems too high, don’t release. If release can be managed by conditions, such as interim supervision by the equivalent of probation officers, go that way.
That is the approach we take in Canada. My Beloved is a Crown prosecutor, and in about 6 years on the job, has only asked for cash bail once. As well, we don’t have bondsmen as a commercial activity - in fact, bondsmen on the US model would be committing a criminal offence here. You can only post bond/surety for another person if you have a personal connexion to them - family, friend, etc. We don’t have bounty hunters, either.