The Aztecs are the most agressive nation here and fight very well.
The Inca can have a very good economy, thus create a nice army, but their UU...
The Spanish have a really good start, but after I don't like them (their bonuses).
The French are really good, can be devastating if well manipulated.
The Russian are rather defensive until late game, too bad imo.
The German are multipurpose and I think could go well with any team.
My preferences would be:
1. Aztec + French
2. Aztec + German
3. Inca + French
4. Inca + German
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