I didn't see any mention of stopping illegal immigrants.
Yes, it needs some work in the area of immigration reform. A separate Article is needed to address increased border security, a means to properly identify and process guest workers, and an initiative through federal law or Constitutional Amendment making English the official language for all 50 states.
There are many fine ideas in the 21st Century Contract with America. When Newt Gingrich speaks, I always listen. I especially appreciate Newt's extensive knowledge of history which is a rare commodity in politics. He is a brilliant man and a wonderful resource for strategic planning among conservatives.