An idea of mine I posted as a reply Nenjin's excellent post earlier this week.
https://forums.elementalgame.com/393162
I like the idea of champions becoming city governors. A brainy npc might become head researcher for example.
When a champion or sovereign enters a city the UI would give various options:
Research: Add Intelligence Mod to kingdom total with towns that have a study.
Arcane Research: Add intelligence modifier if you have an arcane lab.
Training: Speed up training of new troops or increase XP of stationed troops based on Cha and Str.
Practice: Gain experience.
Mercantile: Focus on increasing economy.
Tutor: Train a member of the population in your profession. Such as a Warrior Channeler teaching a peasant how to fight better and become a true warrior rather than just a militiaman or a Miner teaches a peasant how to mine better, blacksmith etc...
Beautify: Artists, bards, or members of royalty can increase the prestige of a city by creating or sponsoring works of art in the populace and by creating a more refined environment encouraging immigration from those who prefer civilization and introducing children to art thus encouraging them when they grow up to become musicians or appreciate beauty. Modifier based on charisma.
Organize: Lower maintenance costs and improve city functioning/government. Wisdom based?
This could then replace the global improvements provided by some champions. A farmer champion would increase food production in that city and could take time out from doing that to tutor an apprentice who could then go off to another city.