2-5 was not a problem for me. 3 Energy collectors, 2 mass accumulators, autocanons + freezers. Spam autocanons and heavy lasers as much as resources allow. For 2-6 use adv fighters and artillery. For 3-2 and further put basic canons in front of your station to draw fire away. 3-4 - supply docs and basic lasers + 1 or two energy fusion cores.
As for the game - hotkeys, shift select. Carrier is quite useless - fighters instantly. 3-2 and above is basically a survival until you breach the defense which totally random.
Great game, it surely has potential.
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