Have you tried leaning into their natures? If they're combat monsters start throwing the world in a loop. Bounties on heads, assassins in their sleep, allies start falling left and right to give them a few days of respite. Only to have the hounds at the door again. In my option that's the terror of stepping on a giants toes.
If they're invested in the game and their characters then just have fun with things.
I ran the system for a few players a while back before 2e, I was able to keep them invested by the world itself. But mine ended around 15 or 16. If you're having doubts ask them