Instead of just flooding the country with more skilled immigrants, we should be encouraging Americans to choose more in-demand career paths through manipulation of tuition rates. For example, if you want a degree in accounting or engineering (which have very high demand), your tuition should be very cheap (maybe even free). If you want to be an "Arts & Crafts" major (meaning political science, history, underwater basketweaving, etc.), it should cost a fortune.
However, I'd give a loophole to those who want to study Arts & Crafts but not have a mountain of debt. If you double major with something in demand, you can still gets your Arts & Crafts degree on the cheap.