I prefer a light on mine. That because of a case I worked involving a drunk 15 year old girl that stumbled into the wrong house. "But officer it was dark and I couldn't see who I was setting on fire and . . . ."
Rule #4 and all--believe it or not the four rules apply in a fight!
Now that you have a shotgun. Go get others. As you use them, they will break.
I also recommend working out with the shotgun. You can work it into your dry fire practice. The pig is heavy and if you have to hold it on someone it will be very heavy. Curls, reverse curls, lat raises, militree presses, sit-ups with it all are good.
Now go out and buy good doors, locks and windows so you never have to use it!