I do agree that Phone Guy should have made an appearance, or rather, a voiced one. He should have been this character you always hear the voice of but never see it.
Maybe a post credit scene where they find him stuffed into a suit but shockingly still alive and he says weakly "I always wondered what were in those empty heads...back there..." (tho its done in an angle we cant see his face). He needs to be mysterious and you are always unsure if he is really on Mike's side or not. You could even add to his backstory and imply he knew about the murders and, out of guilt maybe, remained at freddy's to make sure the haunted bots wouldnt hurt anyone.
There are many directions you could take this integral character we only know the voice of.
Aww man, Markiplier was apparently going to be the security guard who gets sliced up at the start.
I can imagine fans complaining that Mark is "king of Fnaf" and he shouldnt have been given a lowly "opening kill" type character.
Many legit wanted him to play the lead. I can maybe even imagine that happening if Iron Lung wasnt a thing (God knows how that movie will turn out. Its similar to Fnaf that it has such a vague but scary lore that you can take to any direction, for better and worse).
No camera-watching, no door-shutting, not even Freddy doing his music box bit.
I legit expected one of those vandals to run, hide in a dark room and then hear the music box as Freddy's face glows slightly in the background. You could have even done a bit like Dead Space where he glows but so faintly you almost cant see him getting closer and then suddenly he just appears right at his face, doing the familiar screeching sound (almost "replicating" the power outage of the original). It would also make sense since Freddy mostly hides in the dark in the cameras of the original, implying a level of intelligence the other 3 lack.
Hopefully things will be a bit scarier in the sequels. It'd be great if they were rated R, but I know that'll never happen.
Fnaf 3 has the perfect setup for a 80's slasher call back sort of movie. It has a classic setup with short sighted youths messing with a past they have little knowledge or respect for, causing them to unleash a horrifying dormant monster that hunts them down over and over.
In fact, you could do something similar to that scene in Halloween Ressurection where the guy is guiding the girl in the Myers house by watching the cameras in the web show, telling her where Micheal is currently and where to go. We could get a scene with our lead doing the same with some of his friends.
"That thing is in the corridor! I just lured it to the game room! Go go go go."
