This game mode would serve as an alternative to the normal skirmish in which two equal and symmetrical factions establish their base and then fight set piece tank battles over a tiny often symmetrical map.
The unreleaved third faction is hence forth called "URTF" for the sake of keeping this short.
Insurgency game mode would have two factions: the occupiers and the GLA resistence. The occupier players would be either EU or URTF, while the GLA resistance players could only choose the GLA.
The setting would be a very large map with varied landscape and civilian infrastructure. This map would preferably be central asian or middle eastern region. The map would have mountains, fields and a large city surrounded by suburbs and industry. Additionally, this city would have actual traffic and civilian life: not just some pre-placed props, but a self-sustaining program that generates city life, akin to Grand Theft Auto.
The goal of the occupiers (EU/URTF) is to root out the GLA resistence by destroying GLA hideouts and weapons stashes.
The goal of the GLA resistence is to destroy the occupying force by inciting revolt among the civilians, destroying EU/URTF bases, patrols, and so forth.
The GLA resistance would have no central base or conventional base building in this game mode. Instead they would have hideouts and weapon stashes. Both of them would be concealed in the civilian infrastructure and natural terrain. The EU/URTF would have to raid these buildings and search out these woods or capture GLA operatives to interrogate them to provide the location of these hideouts and stashes (a return of the POW system). The GLA would not be able to build new hideouts or stashes, but would be able to move them (if its found) and establish new ones whenever they gain more support from the locals.
The hideouts would provide the GLA with pop limit and special abilities while the stashes would be the production buildings. Both would be up-gradable as the game advances, providing more resources and abilities. These hideouts and stashes would be dispersed all over the map, preferably, because they do not have much defense against EU/URTF assault. Their main protection is their concealment.
Meanwhile, the EU/URTF faction would have bases with some limitations, as these are occupying forces, not front-line combat operations: i.e. no massive tank armies and somewhat limited resources. They would still, however, have an overwhelming advantage in a set-piece battle: so the GLA has to win through subversion and insurgency, rather than confronting the EU/URTF directly.
The EU/URTF forces would have advanced infantry equipment and sophisticated AFVs, while the insurgency would fight with improvised explosive devices, ambush tactics, stealthy sabotage and so forth, even more so than in normal skirmish. GLA would have scarcely any combat vehicles: they would have to mostly rely on infantry, civilian vehicles and bomb cars.
In an open field the EU/URTF infantry would be able to massacre GLA equivalents due to longer range and greater firepower. The resistance would have to try to get close in order to have any measurable effect.
The GLA would, however, be able to conceal their fighters among the civilian population and in the terrain. They would be able to move their forces around in civilian vehicles and avoid detection as they move along with civilian traffic. The EU/URTF would be able to establish road-blocks to inspect this traffic.
The EU/URTF would also be able to raid buildings and organize patrols, both of which have a high chance of detecting nearby GLA activity.
The GLA would be able to hire local informants to keep an eye on EU/URTF traffic. To stay alive, the GLA would have to stay on the move: relocating their hideouts and stashes whenever EU/URTF presence in a region grows too much and likewise, relocating their attacks wherever EU/URTF units are moving.
The GLA would be able to incite uprising in an area where they have established highly upgraded hideouts. This would allow them to raise angry-mobs: which would be the worst thing to happen for the EU/URTF faction because they would not be able to target the angry mobs with lethal weapons. If the EU/URTF targets the angry mobs with, say, bombing runs, this would give massive support for the GLA in terms of funds and new hideouts.
if the EU/URTF faction is too heavy handed and destructive toward the civilian population in their fight against the insurgency, angry mobs and support for the GLA would naturally arise.
This game mod would be an alternative to conventional skirmish, not a replacement. And as such, it would provide a change of pace from normal set-piece tank battles. It would also be fitting since it would allow the game to have an emphasis on the differences between conventional (I.e. EU/URTF) factions and the GLA.
Also, CNC has never really had other game modes besides normal skirmish. Nothing that i can really think of immediately.
Not really sure. Of course it would require heavy coding: which takes time away from other work. Mapping might also take its time, however this game mode would not need more than 2-3 maps, assuming they're large enough.