Single Player GC tip on how to survive early on: Rush to get planets, just not too fast that you can't defend them. I have 1 barracks + 1 light factory on every planet (kessle I max. with land units, sell the factory and barracks, and replace with mining faculties because it has only 2 land spaces) and all the rest is mining faculities. I produce everything(troops, ships, etc.) at 1 planet (defended, is a capitol ship producer planet). So I get a great income and every planet is defended (rebels all planets have garrison of 2x. Troopers, 2x. Plex, Empire: 2x. Stormies, 1x. At-St, 1x Scout AT IMPORTANT PLANETS(producer, and/or high credit value ones) maybe At-At after I have a credit surplus and at Tech 5.)