Hearthpwn

Overall it seems like good changes, although you change the play style considerably by removing Doomsayer + Flame Juggler, as they are in the deck to primarily help with the early game, along with the Argent Squires. Tho you gain traction with an earlier board clear with Pyromancer and/or a 1 AoE token kill. Should play more like regular pure N'Zoth decks.

I'm not a fan of Cairne personally. Seems too slow to have an impact on the board and I don't think he is enough of a threat on turn 10. I think I would rather go with Infested Tauren, for an additional taunt instead of Argus (in particular if you don't have any Squires in the deck). As I said in the thread where I posted the deck, I have an eye on 1 Argus for the longest time and are seeking for options to replace him, so I think I will try that. :)

Brann is natural fit. I play him in my mid-range warlock Zoo'Thun for obvious reasons, but I'm not sure if he has enough valid targets here tho to warrant an inclusion: N'Zoth, C'Thun (and both of these will happen very rarely). Buffing C'Thun is nice and everything, but not worth it to play Brann for. That leaves Emperor and Disciple and 1 Argus, if you don't play Flame Juggler.

I'm not a huge fan of Forbidden Healing in the deck. FH works if you simply want to drag the game out, because you simply win with a full N'Zoth summon or something, but that's not the case here. It's more flexible than LOH, but you gain only "time" by playing it, it doesn't generate new options like LOH does, which is also better to refill your hand late game. I can see 1 working, but not 2. Kinda defeats the purpose of Ragnaros as well. You would also need more card draw without it I feel. Maybe a second Solemn Vigil is needed then. 

Let me know how the deck works. I'm curious. I have a blast playing it and a rather high win rate, in particular against other control oriented decks.