I experimented with a piece of lexan (1/4" thick), painted it black, and attached it to the same area you pointed, but it looked kinda weird (IMO), so I took them off. I hit my bumper a few times, even thought I shattered it one time, but still good. you can notice some scratches where it was hit but not too bad.
notice the black mark on the front lower driver side, I did that on my driveway.
... I did it on both sides.