My top rankings are "Information Quarantine" for the +5 stability and "Nutritional Plenitude" for the extra pop growth and happiness. The worst is imo "Thought Enforcement", with a cost of 300 influence it is already the single most expensive edict in the game and its effects are net negative in my book, +1 encryption and +25% governing ethics attraction are not worth a global -10% happiness modifier.
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