Reworking the Stealth/Detection system

The newly announced Warden mob rewards stealth in a new, refreshing way. It being the first "blind" mob, I started thinking about the role sight plays for other mobs. 

Currently, sight doesn't seem to have much of a role in the way hostile mobs detect you - they could have their backs turned when you enter the detection radius and they would still know you were there. What if mob detection was instead based on a combination of sound and sight? As in, if you are in a mob's line of sight and it's facing you, it's far more likely to detect you than if it's back was turned.

For example, if I am walking or sprinting behind a Hoglin while in its detection range, it will hear me and chase after me. However, if I'm sneaking and not making any noise, I could walk right up to the Hoglin undetected as long as I wasn't in it's line of sight. Perhaps I could even land a sneak attack for extra damage!

With this update would also come the ability to distract mobs by throwing snowballs or eggs in their line of sight. They might go investigate or at least turn their heads so you might escape from behind.

I think this change would give players even more options for getting out of sticky situations, as well as open a world of opportunity for new items and abilities. Maybe there would be a new throwable item that makes more noise, or an armor type that makes you harder to see.