It was a well discussed topic. But, I want to remind some of the inequality amongst civilizations...
1. Building Time:-
As we know, Gauls and Britons have a lowered building time for their weak structures. But conversely this gave them advantage in games. As per history, their knowledge of architecture wasn't well and scientific as like that of others(Romans, Carthaginians, Persians or Greeks). So, it's obvious that their building would be rubble. But, this deduction in 20%