If Scott wasn't the man he was and plan out a story and added the mimic somewhere in the classic games I believe he would be looked upon more fondly story wise. I like Secret of the Mimic, despite it being a FNaF game by name only, it shows the mimic could've had its own unique character that, being honest knowing Scott, isn't going to be explored any farther. Unless Scott goes back and retcons a bunch of the story to clear up loose ends, then the FNaF lore will basically remain the weird mess that it is, especially for the place of the mimic.