[thejeff]

Doesn't it Horror Mark all the slaves? And have a chance of summoning horrors? I haven't used it enough to remember.

Probably want some of those Astral mages to be Horror Marking at the very least.

The other problem I see with that set up for casting Charm is that you don't get to the point of spamming it until the end of the script, so you're relying on the AI to keep casting it.
The astral mage isn't needed, if you're going to use Hellpower anyway. The 1 path boost from PotS is nice, as are the Astral buffs, but it is more fatigue and a weaker off path mage.
If you've set up the masters to cast last, there's no need for them to switch to bows.
I'd also suggest Reinvigoration as the last spell instead of Relief.