We're already taking in a million a year legally, how much more would be enough for you... 10 million, 20 million, how about a billion?
The US is not a job fair, it's our home, and the views of a tiny minority, maybe 1% who have been imposing upon the rest of us an endless wave of humanity, legal or otherwise isn't going to last much longer. After 1924 and the Great Wave we had a 40 year pause to assimiliate and Americanize the new immigrants, it's time for another one.
I would think 3 mil would be plenty, then. a little more than 1% of the US population per year. Of course, the INS (ugh) would need to have the tools to help these folks integrate into America; hook 'em up with local English classes, that sort of thing.
The benefits of legal immigration are tremendous in terms of growing the US economy and adding new blood to the business world, and cracking down on illegal immigration would limit the downside that a lot of folks dread.