1 - Make NPCs own or make something that you need a trebuchet to knock down for some cool reward.
2 - Let clans form trade routes with each other that reap some minor rewards based on some economic formula. Maybe you would be needed to escort the convoy.
3 - I notice thralls have a ‘Level 0’. Let them level up as you have them follow you.
4 - Some sort of fight pit where you can fight waves of opponents to see how far you can get.
Wakrob