The vampire ranking is the simplest you've yet to come by. There are large leaps between each of the ranks, however, and they do not commonly interact

1) Pure blood, vampire born aristocrats (work as City Leaders)
2) Pure blood, vampire born commoners
3) Squalid blood aristocrats (vampire marries human and has baby, for example)
4) Squalid blood commoners
5) Shadows (humans that follow vampires around by magic compulsion because they are addicted to being bitten. They are like controlled servants to the vampire's needs and have no objections)
6) Turned creatures (was another species then bitten to become a vampire)