Filing I-589 for a derivative status

[Maken]

Dear All,

I am curious to know what the pros and cons of being included in I-589 application as a dependent. If included in I-589 as a spouse or child, you are required to appear for the interview. If so, what are the contents of your interview going to be? If already being filed as a dependent, can you modify the file before the interview date?Can you file another application as main applicant if your application as a derivative is denied?