We have advanced to 'B' missions, given only to well-connected Hunters. We can expect to see some more involved jobs, but the rewards are going to be substantially higher as well.
The frequency of 'D' level missions will decrease further.
Of course, there exist 'A' level as well, represented by the Golden Badge. To procure it, however, we gotta 'become noticed by the Four Dragons', whatever that means. It will also cost us a lot of Glamour.