I got into GalCiv3 after Crusade was out, I bought the bundle with all dlc, and have only played Crusade.
Am I missing anything by not playing the base game?
No, as I understand Crusade is an expansion that introduces many more mechanics. The base game has a different play style but it has fewer features. If you go and play it after you have played Crusade, it's going to feel like the game has been cut.
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