Resident Evil 7 is significant not only because its a good game, but also because it represents a return to what the series became famous for initially - tense survival-horror gameplay. Given how Resident Evil 7 turned out it might come as a bit of a surprise to hear that it actually started off as yet another action game, but that's exactly what it was before Executive Producer Jun Takeuchi joined the team and shifted the focus from action onto pure survival.
All of this, and a whole bunch of other interesting details, is covered in the first part of the Resident Evil 7 documentary, so if you wish to peek behind the curtains of game development I would heartily recommend you give it a look. There is some fascinating stuff in there! Here's the video:
I'm kind of sad the zombies that track the player based on their breathing were cut from the game, because that sounds like a downright awesome concept! Having to sneak through a whole bunch of them, constantly weary of your rapidly depleting breath meter, is a great way to introduce tension and really get the player on edge. Unfortunately the concept ended up being too good as players kept holding their breath for prolonged periods of time in real life as well, but I certainly hope this is the sort of thing the developers will revisit in the future.
As for the second part of this documentary, I'm afraid I don't know when its coming out. The only thing I can say is that I hope its going to be soon because learning about what content got axed and why is quite entertaining!