Recruit representative armies, not units I've explained my thoughts on this before. The tech tree would allow the player/AI to build larger and/or more complex and upgraded armies, but the basic elements would be historical. Right now there is no reason to build lower end units once you get the higher end units. And you can build whole armies from elites. But the most interesting part of the campaign is fought early on, with the lowest level units and that makes for a rather bland experience.
More Meaningful Naval Strategy Port upgrade level would allow port defense and require more ships to blockade. Total port level would also determine how many boats could be in the water. Invasion force size would be limited by the number of ships available. Elephant units might require 3 ships per unit, cavalry/camels/chariots 2, infantry 1, family members 1.
Campaigns from different periods A very early campaign at the time of Alexander and the Samnite Wars (with higher resolution Italy map). A later, 3rd Punic War/Marius campaign. A slightly earlier Pyrrhus time period Campaign.
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