Hi! Here is the game concept document of my game. I tried to be as exhaustive as possible. Happy reading 
Synopsis
France, in the not so distant future. The oil refinery in Le Havre is blocked by strikers and other comrades fighting against an unjust legislative reform project. They occupy their work tool to impact the economy and push the government and employers to abort the project.
Faithful to their mission of protecting the interests of the bourgeoisie, the police forces of CRS (Compagnies Républicaines de Sécurité – Republican Security Corps) attacked the site and tried to free up access, so that the precious black gold could once again irrigate again the economy of the country.
We control the struggling proletariat and we must stand up against state violence, repel the police and become stronger.
Core Gameplay
I will stay close to the core gameplay of Realm Rush (positioning of defensive structures, waves of enemies…), with one exception. The goal here is not to kill opponents (they are human after all) but to prevent them from going further.
So our objective is to use our limited resources to block police access to the refinery until the end of their working day – they are French state officials and they must at least follow somes rules – or until their energy is zero (fatigue).
Tech Setup
Platform: PC / Mac / Linux
Aspect Ratio: 1920*1080 16:9
Input: Mouse
Features
Third Person View: I choose an isometric point of view because I like it
Strikers: This is the main resource. They are the comrades who work at the refinery and know how it works.
Comrades: This is the second resource. They are the proletarians who don’t work at the refinery but come to reinforce the blockage.
Materials: This is the third resource, the set of elements that allow physical blocking.
Popular support: This the fourth resource. A blockage is also a media struggle and the objective is to maintain and increase the support of people who are not present on site. Our actions and police actions affect this resource.
Day/Night Cycle: a game starts at 6am (legal police response time) and lasts until dark.
Enemy Paths: the refinery is on a peninsula. Enemies must come from few directions, but have substantial means of intervention.
Stretch Goals
Enemy Pathfinding: Enemies will dynamically change their path, depending of how we block access routes.
Build Timer: barricades and other obstacles will take n-seconds to build.
In addition to the stretch goals suggested by Gary, here are few others that I like:
Persuade colleagues: There are 1,500 people working at the refinery, not all of them are already on strike. While we devote some part of our resources to defending against the police, another part could be used to rally the waverers into fight.
Police the police: The police is violent by nature. To avoid nasty injuries, some structures that we can build allow us to monitor and document the action of the police. Useful for gaining popular support, as long as the police lose it.
I have other ideas in mind (dirtying their equipment, breaking their vehicles, materially and economically weighing on their ability to regenerate…) but I will focus on implementing this one first 
I’m quite excited too 