After getting home and reading through this again, I wanted to say I agree with the "paddocks" area idea. But I know a lot of people are with other friends or people they know, and they tend to hang out in groups, so that may not be a widely accepted solution. Plus, people will always sandbag no matter what.
I guess you just have to play it by ear. I had 3 people in my range asking to race, but I never found them again, so almost all of my runs were paired up at the line.
It was a great track, though. And it was good meeting you.