The most curmudgeonly person is often referred to as being grumpy and irritable. However, the antonyms of this word describe people who are cheerful, pleasant, and friendly. Some appropriate antonyms for "most curmudgeonly" could be happy, lively, sociable, warm, and amiable. These individuals may be described as genial, jolly, affable, or gracious. They tend to have a positive outlook on life and enjoy the company of others. Rather than complaining and nitpicking, these people are often admired for their optimism and kindness. Overall, the antonyms of "most curmudgeonly" describe individuals who are a delight to be around and bring joy into the lives of those they encounter.