4) Don't always believe what the "Ship Builder" stats are telling you. I found a number of times that, once built and out in the real world, my ships do a lot more damage than the editor told me. This is in part to some techs that give Blanket boosts.
Well the ship builder shows you the raw attack and defense value of the ship, without any bonuses you might have in "weapons" and "defense" categories. Such bonuses are found in anomalies, military ressources, around military starbases with dedicated modules, techs, onboard ship offense and defense boosters modules, and race ability.