The phrase "more fire-eating" is often used to describe someone who is extremely passionate, bold, or aggressive in their beliefs or actions. Some appropriate antonyms for this phrase might include mild-mannered, cautious, or diplomatic. A mild-mannered person is someone who tends to be reserved and low-key, avoiding confrontation or highly-charged situations whenever possible. A cautious person is someone who approaches things with care and consideration, weighing the potential risks and benefits before taking action. Finally, a diplomatic person is someone who is skilled at negotiation and finding common ground, making an effort to avoid conflict and foster harmony between different groups or individuals.