The nominal reason that being part of a racial minority should give preferential treatment in the admissions process is the extra educational challenges that such minorities face. The logic is that race correlates well with these educational challenges, which is reasonably fair as far as it goes. Basically like jhaugh's 'corrected personal brilliance' metric.
So what you'd really like to do, if possible, would be to stop measuring race, which provides only a decent correlation, and start measuring those educational challenges more directly. As it turns out, we have a pretty decent way to do that -- standardized test scores are used for admissions anyway, so it's just a matter of determining, say, the average SAT and ACT scores for a given school and determining how the individual student's score compares. So a 1400 SAT, while it's not bad at a place like Stuyvesant, would have even more weight in the admissions process at a place where the average SAT score was in the 800s...
You could argue that this penalizes students in very good schools since they can't compete with the same score from somebody from a worse school... But then, they've had the extra educational opportunities, so they should be scoring better than somebody equally intelligent. And I think the number of people with 1400+ SAT scores from horrendous schools is pretty limited, so it's not like good students from the best schools will be thrown out en masse. Those who *will* be penalized are the worse students from the best schools, which seems reasonable -- they're surrounded by the best available resources and still aren't making much of a showing.
So the argument that minorities are often poor, causing underfunded schools, causing less-educated students would be dealt with nicely. If that's true and the schools are of lower quality then the average standardized test scores will be very low, which will give an admissions boost to the best students from that school. And that'll be true regardless of race, and in a colorblind way.
The biggest downside I'm seeing is that by the time the graduates of such a program got old, their stories about how poor and downtrodden their upbringing was will get even more obnoxious. That's a risk I'm prepared to take.
Anyway. Not that it matters.