One thing I don't like about Civ 5 is how each unit can only need 1 resource to be built. In civ 4 units could actually need more than just 1. For example, a WW2 era tank needed oil, while a modern tank needed both oil and aluminium. This meant that oil was still needed in the information era. But in Civ 5, modern units only need aluminium. Is there anything else to do with oil in the information era? Or does it just become worthless? I suggest a new building called "petrol generator" be added into the game that unlocks once you research combustion in the modern era. It would basically work like a watered-down nuclear plant, offering a production bonus and extra with each building costing 1 oil. In this way, oil would still be useful in the end game. Thoughts?