I would hate to read a story where everything a character said is written as the accent sounds. It would just really annoy me. I think that the best way to show that a character has an accent is to put the accent in the dialogue once in a while, and to make sure that the readers know that the character has an accent. In my opinion writting a characters dialogue the way the accent sounds would really affect they story in a bad way. I am not sure if I would be able to even read the story.
I hope all is well with you.
Kurt