There is one fatal flaw with your idea. That is, that the whole point of the TW games, is have WAR! No one could really care about making documents and powerpoints, all they want to do is build a empire, make armies, have huge battles, and conquer the world, hence the name TOTAL WAR. Diplomacy was put there because it would be realistic. And besides, what would think is cooler, watching your infantry charge into the enemy line, while your archers use fire arrows, while your siege engines take down the enemie's walls, or giving a document to some other country and hoping that will pass your law?
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