Suggestion to add more diverse parties on the world map. Cultists, wandering nobels, woodcutters in the forest. Some if being attacked may make settlements hostile, some are just dangerous or may interract with your mercenaries and join the band.
For example, meeting lost woodcutters that have being attacked by schrats or direwolfs in the forest. They are running away and can trigger a quest or just a situation with a reward.
Vagrant cultits on the road can reach a settlement and change the settlement situation or meet your band and draw your dumb or superstitious brothers in their sect. You can try to fight back in a dangerous battle or just go your way without merceneries.
Maybe you could just create new similar quests for contracts.