The antonyms for the phrase "more thought out" could be "impulsive," "haphazard," "spontaneous," or "unplanned." All these words indicate a lack of consideration, planning, or preparation in carrying out an action or decision. An impulsive action is done without thinking, often based on sudden emotion or impulse. Haphazard refers to something done without any method or order, and can imply a lack of effort or care. Spontaneous, on the other hand, suggests an action or idea that occurs in the moment without prior thought or planning. Lastly, unplanned can be a complete opposite of more thought out since it indicates an absence of preparation or foresight.