There's a minigame that's shown up in a couple of places that I've liked playing, sending agents to run missions.

Some benevolent entity wants stuff done, and will reward you for doing it. You pick an available job/task/mission, assign some of your people to it, and wait for the random number generator to decide your fate.

The skill/challenge/fun comes from matching your people to tasks - Peter is a fighter, Joan is a diplomat, so send Peter to hunt deer/fight zombies, and Joan gets the negotiation jobs.

You must also manage opportunity costs - if Peter has been assigned hunting duties, they can't enter into a competition that there'd easily win.

More complex versions can bring in resource management. Peter brings back a boar from a hunt, +5 food, but took damage so -1 medicine, and they can't be assigned for a day or two.

Early on, missions can be simple templates: "The local village is being attacked by (zombies|robots|frogs), kill n for a reward from the mayor", but I kind the idea that there is a world behind the missions - hunt too many wolves and the local deer population jumps up, but that leads to overgrazing and damage to young trees.

The flow of time also needs to be modelled. Is there a 1:1 match between mission time and real time, or do missions run faster (or slower!).

How does the player interact? A point and click webpage would work fine, but maybe play by email? (Especially for something with a more sci-fi or espionage skin).