As a photographer, what do you think are the advantages and disadvantages of a large aperture lens?

Aperture has two main functions, controlling the amount of light and depth of field. A large aperture will have more light and less depth of field. With more light, you can use smaller ISO to get better picture quality. With more light, the shutter speed will be faster and the subject can be "solidified" better. With a small depth of field, the subject will "stand out" from the blurred background and give the subject a sense of space from the blurred foreground. Well, that's the advantage of a large aperture.