I understand the idea of first person point of view since the writer is telling the story, right from the mouth of the main character so you know exactly how he or she feels about anything. However, it’s hard to know how anyone else is feeling unless the main character can describe the actions or behaviour of the characters, and even then it would be biased.
I have read some good first person stories and I have even thought of writing a story like that, but it’s not my favorite choice. I like writing and reading third person stories because you get to find out what many characters are thinking. Although you have a main character, the minor characters help to propel the story so why not know what the others are thinking.
If written properly, you won’t inundate the reader with so many thoughts but will inform and entertain.