Yeah, I've got about 29k HP unbuffed for 10 man Maly, and will have Fort/Kings/Commanding Shout/Flask/Food -- so I should be in the high 30's, which should be enough HP. We're a touch light on our DPS overall, and I want to make sure I'm not threat capping the 2-3 very strong DPS who we have when they're stacking the spark buff so we can move into phase II/III faster.
Improved Spell Reflect is for the Scions' Arcane Barrage in phase II.
This'll be my first shot tackling the big blue dragon (been waiting on the guild to catch up), so I'm looking forward to it. :)