When would I use First-person or Third-person Narrative?

I would use first-person perspective when I want to give the reader a sense of reading through the person's eyes and putting himself in the character's shoes by thinking what he thinks but not knowing how other characters think. This pushs the reader's curiosity forward to read on as he doesnt know what will happen next and creating a sense of suspence. The first-person perspective also makes the reader be closer to the character as the reader reads his mind and sees his behaviour. I would probably use this perspective when the main character is a bad guy / when the story is a mystery or action-packed story.

I would use third-person perspective when I want the reader to know everyone's thoughts and see the story at everyone's perspective. This perspective also makes the writer easier to describe the characters without sounding awkard(eg. Sweat rolled down my cheeks). This also causes the reader to see from a utilitarian perspective, trying to achieve the greatest happinness for everyone as the reader can read the character's thoughts and know their motives. Third-person perspective also allow the reader to see more about the setting but will not know each character very well, unlike the first-person perspective. I will probably use this when I want to develop the plot in storys involving relationships or conflicts between the characters.