The antonyms for the phrase "more straight-faced" include jocular, humorous, playful, lighthearted, and jovial. These words indicate a person who is not serious or solemn and is instead humorous, cheerful, or amusing. The opposite of being straight-faced can be a helpful way to express oneself, particularly in social settings where tension and angst can be reduced using casual language, humor, and friendliness. Using antonyms like jovial, humorous, and playful can help to create a lighter and more joyful atmosphere, fostering a jovial mood that encourages people to connect and interact with each other in meaningful ways.