Rear-ended - Minor Damage. Fix it or Let it Go?

This morning, as I am leaving my subdivision I wait at the stop sign to pull onto the main road. Someone is behind me, waiting too. After about 10 seconds of waiting at the stop sign waiting for cars to pass, I get hit. It couldn't have been more than 5mph.

Now, the guy was pretty apologetic. I called the cops for a report etc, got his insurance, DL stuff etc etc. But, should I even go through with the insurance fixing it or just let it go? The damage is minor, but there nonetheless (I'm borderline anal and a perfectionist) but I am wondering if it is minor enough to just let it slide.

I already have a ding on the front bumper from sliding into a parked car during a 2010 ice storm, now this on the rear bumper. I don't want to start letting too many things slide and eventually have the car start turning to shit.

Its a 2008 WRX with 76k on it.

I let my insurance know about it, but I wanted to get opinions before calling his insurance to file the claim.

Its hard to see the exact damage in the pics, but theres a dent from the support and some scrapes and scuffs which I am sure will come out with rubbing compound, etc.

One coworker told me to let it go. Another told me to get it fix because I will be penalized for value when I go to trade/sell it down the line.