If you take the HoZ over the Moser's, you're losing Fireball effectivness, but gaining in effectiveness for FoH. If you go that route, you can take the Conviction down to 12 points.

Without the 5/20's, you're going to be a little low on resists, even with the swap to HoZ. Moonfall is a nice idea for the synergy, but then you're REALLY hurting for resists. If you swap out for Ormus, you'll need a LOT more STR for the build, and you lose Teleport and R/W.

I did that build to make it flexible, not to sit still and throw fireballs.