I was thinking that taking the Dwarf Fortress model of having a population of labourers under your influence and then setting up jobs that they then do when/if they can and in the order they feel like it due to fairly complex decision making algorithms and applying it to other situations would make for some damn good games. This is especially true if said ripoffs where a little more accessable to a wider audience UI-wise.
The Orion Belt
My first idea in this vein was to make a game about a group of Marsian colonists who have to colonize an asteroid belt. Colonists who aren't wearing spacesuits equiped with oxygen can't travel outside and must stay inside of habitation pods or the mines that reach into the asteroids below them. This brings a new danger to miners. Dwarfs can flood a mine with water or lava, but only Marsians can accidently breach and depressurize one, sucking its contents into the cold reaches of outer space. Transport pods are necessary to traverse between asteroids unless costly interasteroid bridges or ziplines are made. Inside your colonies you can farm food, produce oxygen and building materials or gizmos, etc. On the outer surfaces you can hunt wild bugaloo, etc.
Zombie Fortress
This one I like even better, where your underlings are human suvivors of a zombiepocalypse. You can start your Zombie Fortress in the middle of a destroyed urban area, in the country, in a mall, wherever. You must forage for food and resources and use tools to modify the surrounding area into a defensable fortress. You can destroy stairways, build barricades, board up windows, while all the while sending out scavaging parties to find food, weapons, tools and other needed materials and resources.
Appart from zombies and other terrors, migrants will flock to your secured location too. Is one of them a doctor or nurse? Set up an infirmary so you lose less survivors to zombie inflicted injuries and other sicknesses. Do you have land for a farm? Start one. Set up a firing range and barracks for your militia so you'll have the security force you need when ever an Overlord let zombie attack or crazy biker raid occurs. Also, watch out for tremor worms.
If your fortess becomes comprimised, run for it. Set up a way point for fleeing refugees and start an other fortress.