CC2 uses credits in place of raw materials. You gain income credits by shooting things or by capturing and owning islands over time.

You might have a huge chain of islands, with idle factories but not enough credits to build anything for a few minutes.

While this simple model works for the game generally it could be done a little differently.

Island Resources

Each island type has a different set of basic resources, the factory was put there after-all because that island was ideal for that kind of factory. Say..

Factory Type	Resource production rate per minute
Fuel	Chemical x1
Utility	Metal x1 Composites x1 Chemical x1
Air	Metal x4 Composites x3 Chemical x1
Land	Metal x3 Chemical x1
Heavy Munitions	Metal x2 Chemical x3
Light Munitions	Metal x1 Chemical x1
Turret	Metal x2 Composites x1

Perhaps something like that.

Over time, each island produces these materials. Perhaps each island starts the game with a small stockpile, and has a max stockpile it can hold. Islands would probably not start producing resources until it becomes player owned.

Building an item would then not cost credits, it could cost stocked resources. eg

Item	Cost
Manta	3x Metal 4x Composites
Razorbill	1x Metal 1x Composites 1x Chemical
Petrel	3x Metal 2x Chemical
Albatross	1x Metal 2x Composites
Seal	1x Metal 1x Chemical
Bear	3x Metal 1x Chemical
30mm ammo	0.05x Metal 0.05x Chemical

Additionally, Islands with higher shield counts would produce resources faster. A 3-sheild would produce 3x more resources than a 1-shield.

This would give more of a reason to go for a 3-shield air island than a nearby 1-shield one.