Main event - a premium titlefight. So no WMMA or Flyweight or dominant champs beating nr. 7 guys.
Co-main - a pretty strong male titlefight, so like Rory vs Lawler, or Maia vs Woodley.
Third fight - a strong nr.1 contender match (no flyweights or WMMA) , or a flyweight or WMMA titlefight.
Second fight of the card - a good old slobberknocker between two top 6 guys who are potentially fighting for a titleshot or are getting really close.
Opening fight - a strong opener by two top 10 guys that are climbing the ranks. Or perhaps an easy match-up for an elite fighter. Like OVereem fighting Hunt or Frankie fighting Yair.
So no WMMA or Flyweight fights except if they're titlefights.