The term "more well-thought-out" implies that there is a level of consideration and planning put into something. Therefore, antonyms for this phrase would indicate a lack of consideration or thought. Some possible antonyms include rushed, impulsive, hasty, careless, thoughtless, reckless, and irresponsible. These terms describe actions or decisions made without careful consideration or planning, which can lead to negative outcomes. While it is important to be efficient and make quick decisions, taking the time to think things through can often lead to better results in the long run.