Screw night sights/tac light. Learn to shoot without. If anything, a laser would help in a home defense situation, that way you can just look where the laser is and shoot, plus allow for a shot you might not otherwise be able to take due to being hunkered down with a weird angle. Only downside is the BG tracing your line back.

If you want a light, get $30 Romisen. You'll be able to light up the room, blind the BG, and also hold the light to your side or elsewhere other than in front of your face, which is where your gun will be when aiming with a light. If fortunate enough, BG will shoot at the light at your side and not at your body.

Just my 2 cents, I'm in no way an expert in tactical defense.