@Alkhemia: Hm, how to describe it... Delin is part of about 4-6 giant creatures that have their own wildlands. It's not required to kill them but the loot you gain from them is usually very good. There is one wildlands that is a goal to win the game, but we've neither seen that one nor have I ever taken that route so I can't say what it's like though I do know it is a series of 3 quests one after the other.
I was really contemplating whether I could take him on before... all that happened.
@Hanzoku: I do have the money for a second group, and actually have been using one to protect my cities to the west. However, without a hero to lead them I'm hesitant to put them up against anything really challanging. As you've seen, I've been winning battles because I prevent the enemy from hitting me at all, if it was a slugging match then I would be having many more casualties like with the spiders.
@Neonivek: As far as I know there isn't, though I can get a factions sovereign as a hero if they become a vassel to me. Umber can build a unit called a Sion which is a single model unit that gains levels like a champion, but can't use the weapons, armour or items I've been finding.
"Path of the Govener" is used for promoting city growth. It decreases unrest and I think increases growth and gildar generation while the hero is present within the city. It's not useless, but with 3 heroes I prefer to have them active in the world rather then sitting in a town.