So it's a zombie game. But the idea is a combination base/town builder and tactic game.
So you start in a small area. Like maybe just a house as your base. And the goal is the expand out from that house and try and recruit more people.
Combat zones would be beyond the walls and inside of buildings. Combat would be tactics style. And if you move out your barriers to include more space, you would have to make sure to clear out the new buildings of zombies or else they will come out and destroy things and hurt/kill your inhabitants.
Skills would have three sub-sections.
Knowledge
Aptitude
Experience
Knowledge would be how much information you have on this. It would have 5 levels and percentage base. So level 1 is super basic stuff while level 5 would be super advanced stuff. Inhabitants would have certain knowledge levels for each skill. But they can learn more from things like notebooks, computer storage devices etc. Also, an inhabitant can store their knowledge if you have the space in notebooks and/or computers where then other inhabitant can learn that knowledge level.
Aptitude is just what it sounds, their aptitude for that skill and how quickly they gain experience for that skill. It could also potentially be how high of knowledge and experience they can go for that skill. I'm not sure on that. I'm also note sure if I would include a system to raise aptitude through things like drugs/genetic engineering.
Experience is how experienced they are in that skill. For certain tasks, they need a certain knowledge and experience level. And they wouldn't be able to move their experience beyond the knowledge level and possible aptitude level.
Skills would be split between crafting, combat, and support.
Inhabitants. You would start with a limited number. You would need to expand by either procreating, or by attracting further ones with a better quality base and an attractive life. Ones you procreate, would get certain aptitude from their parents but no knowledge and experience. As they grow up with their parents, they will naturally gain their knowledge to a certain level.
The ones you attract would have certain traits. Possibly how you attract them would affect what type of traits.
Trust. Their would be a trust mechanic in the game. So when a new inhabitant comes, they would be neutral, with certain things that could affect it. And they would be unwilling to share their knowledge and become a full fledged citizens of your city until they trust you. I'm also thing alternatively you could jail them and torture them for your information.
So you could be a benevolent society, or you could be oppressive etc. Each would have pros and cons (higher sanctification for higher resource consumption, etc.) Also if the citizen's are unhappy, they could potentially spread information that makes it hard for your to recruit more and even leave. But you'll also be able to prevent the spread of information. You could also make everyone equal or set up tiers of citizen's etc.