remove the stealth bar, kinda. ok this sounds strange but wait ill start with what its like if you just started the game. you spawn in, loot the house, then go to the road. instead of a little white arrow pointing at the enemy, you would get an effect on your screen kinda like the spider sense from spiderman ps4, it would be like your survival instincts telling you there is danger. there would be no arrow pointing to the enemy, and no bar telling you how close it is too seeing you. would make stealth more intense. when you meet your first hunter, it would have a guaranteed drop of a device (idk what it would be called).
This device is what the machines use to communicate and send machines places. with it you would be able to see if a machine is within the distance of seeing you and a general direction. maybe it would be a binocular attachment, making those more useful. there would be a more advanced version dropped from tanks that can see the status of machines, and would work more like current stealth. this would add suspense, not knowing if the thing is seeing you, only knowing it by the sounds it makes and the color of its light.