I run my 400MH a little high, 18-20" off the tops, but if I have a girl that runs away I use the "Hand" method for judging just how close I can let her get. If I hold my hand at the level of the plant and it's not uncomfortable then the plant should be just fine too.

The HinduSkunk looks a little heat stressed from the light being too low, but everything looks good now.

As for the reflective,.... the kinda quilted stuff your running now will diffuse the light better so you won't have so many hot spots. I use Panda since it also helps reduce reflected heat.