The antonyms for "more conspiratorial" would be adjectives that suggest the opposite of secretive or covert cooperation for an illegal or harmful purpose. Possible antonyms could be terms like open, transparent, straightforward, sincere, direct, or reliable. These expressions point towards a more straightforward and honest way of interacting or expressing oneself, without concealing motives or agendas. On the other hand, the term "conspiratorial" implies a sense of intrigue, plotting, or suspicion, which can lead to harm, deception or mistrust. Therefore, using antonyms to describe behavior, communication, or actions can convey a positive and trustworthy impression of a person, group, or organization.