There are some mechanics in the game which I feel like the player is unable to fully interact with, especially in the Beasts faction. Some way in which to fight together with beasts would be really good. Here is my suggestion, but any way I can protect a hexe, follow the destruction trail of an unhold or stuff a nachzehrer would be great. This holds true for other factions like the greenskins.
An endgame crisis or a continuous conflict where the witch covens (e.g. hexes, alps, webknechts, unholds) go to war with the necromancers guild (e.g. necromancers, geists, fallen heroes, nachzehrers) would be a really cool way to implement that. You could fight for and against both sides at the same time filling different contracts for both, betray/get betrayed without loosing renown and create conflict on how to split the loot. It will also add more entities to interact with other than settlements and noble houses.
A similar opportunity to betray the noble houses in the greenskins invasion in exchange for a named piece of equipment would be fun.