I got a pretty stable society by postulating that there are about 500 people of level 16+ in the world, and about 10000 of level 11+ (plus a few noncombatants), and a lot more in the 5-10 range. And about half of those high level people would be genuinely loial to something (a nation, a religion, a cause) and fight for it even without much reward, while the other half were for hire, for those who could afford them. I further postulated that it is possible to make a safe room that high level people cannot break in, no matter how hard they try. at least, not a small group and not in a short time.

this way, a single high level adventuring party cannot overtake a kingdom. they could certainly waltz into a throne room and kidnap a king (the safe room is not the throne room; too many people getting in and out. and the high level people are not on guard. too few of them to stay on 24/7 duty). but the kingdom has certainly mechanisms in place to keep functioning without the king. and you can't get the tresaury - that's what into the safe room. you also can't kill their higher level combatants - they also generally sleep into the safe room. so, the nation has full strenght to retaliate. and it has an army of mid level casters to cast divinations, and lots of spies to gather information in a way that's more mundane, but also more difficult to block with magic. and while the kingdom cannot field anyone who's individually as powerful as you, it can field 50 to 100 people of level 11+; still strong enough to hurt you. Plus, since it still has money, it can also hire more high level adventurers if needed. It can call on allies, and allies will come, because absolutely no nation likes a group of rogue adventurers messing with governments. And all you have for your effort is the king. who won't be any use because the kingdom will just appoint a new one if needed. and if he cannot be resurrected.
You could try the subtle approach of using compulsion on important people instead, but that's so easy to discover with even low magic security that it's not even worth mentioning.

On the other hand, in my world nobody uses conventional armies anymore. when both sides have access to a few dozens high level people with scry and die tactics, a bunch of grunts who need to march on their legs and will die by the scores for a single spell are not worth their cost. golems are used instead. expensive to make, but they will keep on forever without need to eat or getting paid, and they are strong enough to bother even high level people.
The regular people that would otherwise end up in your army? you put them back to work. if they can raise the funds to pay for one more golem, or to hire one more high level freelancer, they ended up more useful that they'd ever have been wielding a pointy stick