There are several synonyms for the phrase "become more open." One term is to "open up," meaning to become more communicative or reveal one's thoughts and feelings. Another synonym is to "disclose," which implies sharing sensitive or confidential information with others. "Reveal" is a similar term that suggests unveiling something previously hidden or unknown. The term "unfold" can also be used to describe the act of opening up or revealing oneself gradually over time. Lastly, "come out" can be used to describe someone who is finally sharing their true identity or beliefs after concealing them for some time.