2. Get dangerous people -- perhaps with little to lose if they are already facing serious charges -- off the street faster
Of course these benefits need to be balanced against the costs imposed on the defendent (who has not been convicted yet).
How does bail achieve that? If they are too dangerous to release, then it's no bail. If they are possibly dangerous, you're letting a financially motivated (exploitative) or ignorant entity decide who gets out of jail...be it a financial institution or the mob or family, but only if you come from a background which has finances to leverage. It's an effective tax on the poor innocent and guilty alike.
In the new system, dangerous people won't be released, regardless of how much money they have.
Bail means that poor dangerous and poor non-dangerous people are detained, and rich dangerous and rich non-dangerous people are released. It's not clear to me that the reason you stated is actually produced by the bail system.
> Get people to show up for trial
I'd be very interested in some numbers backing this up; surely there is some effect here, but I have no idea if bail would make 1% of people or 99% of people show up that would otherwise skip a court appearance.
My gut feel is that if you're impulsive enough to skip a court date and incur a police warrant, the threat of losing your bail bond isn't going to make much of a difference.
I did a quick Google search which brought up this paper from the 70s:
https://www.ncjrs.gov/pdffiles1/Digitization/32349NCJRS.pdf
"A random sample of 756 defendants released on bail in Charlotte, North Caro1ina in 1973 was studied to determine the relative importance of various factors in determining the likelihood that a bailed defendant will fail to appear in court... The most important factors were found to be court disposition time (the amount of time between release on bail and court disposition), criminal record, and form of bail... Comparison of various forms of bail were made, adjusting simultaneously for criminal history and court disposition time. Forms of bail that rely solely on the threat of financial loss to ensure appearance in court proved to be the worst in terms of rates of nonappearance and rearrest. "
I'm sure there's a criminal justice system expert around here that can comment on some more recent research.