A home defense situation really means contact distance out to twenty feet. A pistol would be a better choice. No sights at all are needed indoors most of the time, the target is usually that close.
Set up the gun to hunt, leave the light for the bedstand pistol, and enjoy carrying it in the field. Bumping around in narrow hallways, around door openings, and grappling with intruders is really specialty work, and training in bare hand CQB is a lot of what will really happen. Suddenly waking up to discover an intruder in the room is a huge statement about clueless home security.
Intruders NOT getting into homes is the correct response to actual insecurity problems, and the #1 cure for that is moving out of that neighborhood. When that can't happen, locking the doors, putting in lights, keeping shrubbery down around the entrances, having open views instead of being hidden from the road, even a dog is first - and training in what to do, not what last resort firearm might be needed.
Goes back to the pistol - anything the AR can do, the pistol can and will do better in the home. That's why it's the first choice of professionals. The AR is the long distance solution to use before they even get in - and that is by keeping it out of sight of casual visitors, who are the #1 source of who steals firearms while you are away.