With PvE modifiers being discussed, I think it would be interesting to see some other hive fleets be added as modifiers. They could be mission specific or broad modifiers that chance the color palette and spawns to better suite the tactics of a particular hive fleet.


For example we could have a Trygon mission specific Hive fleet Jormungandr modifier that spawns in more Raveners then other extremis enemies; Or maybe a broad Hive fleet Hydra modifier with very little extremis spawns but double the warriors and gaunts. 


I believe this would not only give the players a challenge in changing the tactics of the enemy, but it would also give more representation to the older hive fleets. As well as deepen the newer players lore knowledge of the Tyranid “factions” this will also allow more knowledgeable players to see their favored hive fleet in game.