Similar to Franks idea, but a more complicated one. Lets say we fill two servers and people are distributed randomly (not taking membership into account). After qualifications, very likely on both servers you get two groups of drivers (fast and slower) and the time diff can be as high as 3-5 secs per lap. I know that we race together to learn from the best, but with such a gap, by the end of lap 3 we, slower drivers, are left on the back of the grid by miles. And then it turns into solitary driving lesson. Yea, consistency (the slower, the more consistent) and other drivers errors might get you nearer to the front pack, but one is driving alone for the greater part of the race.
If we could range people according to some sort of performance points, it would result in a more even distribution of race knowledge. That way, two servers would be a faster and a slower one and upon applying for the grid position, one could have opted for one of them or be classified on performance points in one of the two servers. The end result would be closer racing and more enjoyable experience.
The other way would be distribution upon quali results but that would mean another password sent and extended waiting time between end of quali and begin of the race. Above that, increase in administration, so out of the question.