Why forfeit it to the Feds? They are the ones who aren't doing their jobs! Forfeit directly to the agency bearing the costs.
That's a great idea for workers, what about bringing their kids in. Now you know all the costs associated with pregnant women, births and little kids. How do you handle them?
Same way. 5K a pop if they wish to stay. Want to come here and have babies; sure put up $10K one for the mom, one for the kid.
If they do something that exceeds their bonds they are persona non grata; deportation begins if they do stupid things and are not here to work. If they are working; it may take a few years of labor to save to bond out the rest of the family,but it would be doable. They would have a stake in being law abiding and healthy, and it would be less expensive to transition to being a "legal immigrant" allow them time to do the paperwork, medicals and background investigations that are done with the legals.
The point is if they come and want to stay they pay their way either out of pocket or their employer.
That would be the incentive to participate fish/cut bait.
Another way would be to put a 30% tax on all money transfers under $5k out of the US without some sort of citizenship documentation. This would be another incentive to be legal and get documented.
Get your documents, post your bond, allow free travel for the documented through established ports of entry.
Smuggling? -C ya you or your employer just lost/forfeited $5000 no questions asked.
Want to go home, no problem, show me your bond card if you want back in.
Taxing the hell out of Postal Money orders and Money Orders and Bank transfers under $5000 would put an end real quick to the illegals.
And you could use a Visa/MC type card to track them.