There are ways. You could make it so that cosmite can't be stockpiled. If you lose heavily moded units, your cosmite simply becames available for new mods.Yes, the snowball mechanic in this game is terrible. A surprise loss is typically curtains for you. The cosmite system did really contribute to the issues of this game, way more than it should have. Not sure exactly how they overcome this, as the battle between smooth, workable build caps is near-impossible to figure out. These games typically have one moment where power scaling gets out of control and that is it. This one seems the same, unintentionally.
Oh well. The elephant graveyard of video games is full of titles with the best intentions.
You could make that you also spend cosmite on city "upkeep", which will serve as a brake on going infinitely wide.
You could make upkeep of units increase after a while, so that faction with twice as many cities can't afford twice as many units, but only 1.5, for example, effectively making an alliance of two factions with 4 cities stronger than a single faction with 8 cities.
Also, I'd reduce the number of mods per unit to max 2, or even 1. We really shouldn't be able to tailor units, min weakness and max strength to that degree.
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