A colleague at work asked the other day what I thought about the various modifications that some people do to an AR-15 platform. I see guys at the range that have so many accessories hung on their sporting rifles it makes them look like something out of Star Wars and adds weight that tells me they have never had to hump it ant farther than the car to the range.
I agree with Kyle Lamb and Larry Vickers, only add accessories that enhance functionality and the ability to deliver accurate fire.
The AR below is a good example of this, it has a Aim Point PRO red dot with a Daniel Defense A2 back up site, Magpull MOE carbine stock, Tango Down vertical grip, Bravo Company improved charging handle and a Troy railed fore end. The only I might add is a white light for home defense illumination. This rifle is almost identical to one of the ones I have configured.
This is of course my own personal opinion, there is know wrong thing to add or modify with the unbelievable number of parts that are available. So do what you like and enjoy the sport.