Why not offer an option for immigrants to fast track their citizenship by serving in the military for a period of time. (Say 4 years) This service would give them citizenship as well as teach them a skill that would help them enter the workforce when completed.
This "Service For Liberty" option would only work for those who have:
1. Learned English.
2. Has a clear background check.
3. If already in the U.S., pay penalty (which could come from paycheck and given to border protection budget).
This is meant to be a launching pad for discussion.