I'm not using evidence from the book, but I can explain how the first person affects the story and reader. You can add the evidence when I give you the prompt answer. - First person point of view affects the story and reader because of the different it makes to the plot and whole setup of the story. First person changes the way the story is set up because it is one of the characters narrating the story. It affects the reader because when you are reading the book, you feel like you are the character in the story. It makes reading the story more enjoyable.
Some of the elements which can be considered to be gothic in "the pit and the pendulum" are darkness, internal struggle, horror and terror experienced by the main character, lack of freedom, torture, etc.
I personally believe that other opinions should not affect our choices and/or destiny. Or destiny should be determined by our own opinions and choices.