Yeah I think the moment you stop being a noob and start being a normal player is when you figure out how good trading is.
Gathering Storm just adds goals
Rebel vs. Imperium adds takeover powers, where you can take over another player's military world if you have a ton of military power (most people prefer to play without this, myself included)
Brink of War adds prestige which is a new type of victory point. When you have the most prestige, you get a free extra vp chip every round and sometimes a free card.
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People who don't finish their sentences
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