I feel like the problem with bail is that you have to actually come up with the money. Can't they get the same effect with just the promise of a fine?
So like you say... "Ok... You're released pending trial, but if you skip out and run, you're going to have a fine added that's equal to $10,000 or 50% of your net wealth, whichever is cheaper"...
That's all bail is really doing. Bail just forces people to come up with the money in advance and this creates an inequity. If it's just a fine for if you don't show up at trial or something, you no longer have that problem.
If they skip town, you can make the fine as big as you want, you're still not going to be able to collect it. They're already gone. That's why bail is money up front.