Hearthpwn

Well I don't play much constructed, I mostly play arena, and when I do play constructed I don't only play a single deck, I change it up quite a lot so my rank wont really represent the strength of the deck in any way.
But if you must know I'm currently at rank 13 and from the games I have played with the latest iteration of the deck while I've had the deck tracker on, my score has been 12-4, that's including my Heroic Brawl run last night which went 8-3.
This version of the deck that I have here I only have 10 recorded games in the deck tracker with and the score is 7-3, so yeah, a pretty high win rate, but a small sample size for sure.

The games often take a really long time which is partly the reason for the low sample size, other reasons are that I mostly play arena and when I do play constructed I don't only play this deck, but also at least 2-3 other decks about as much.

 Also I mostly use the deck tracker when I play arena, I don't always have it on when I play constructed.

I swapped few cards:

Raza the Chained ---> Entomb (In most cases 2 or 0 mana won't matter, good card, but not that effective while Entomb is must have imo)

Azure Drake ---> Spiritsinger Umbra (Synergy, drake SD for 3 cards is meh, I didn't have problems with card draw too)

Piloted Sky Golem ---> Kel'Thuzad (I just love this card too much and I would rather pick Cairne Bloodhoof anyway since it's safer and more stable pick)

And I actually like it more, helped me with my deck, try it out too ;)

Raza the Chained is indeed not crucial, but I really like how it lets you still heal every single turn no matter what, so after you've played it you're not like in the situation where you really need to heal face, but then can't play something if you do.
Also let's you combine like 6 + 4/3 or two 5 drops in the late game without sacrificing the heal that turn, but yeah like I said it's not crucial, only convenient and I like using it :)

Entomb has proven itself very useful tho so should indeed run one of those, I will update the list soon, still playtesting some changes.

Azure Drake is not essential to the deck either, it was just a filler and I don't have Spiritsinger Umbra myself so haven't gotten to try her out, let me know how she performs, I've heard both good and bad things about her usefulness.

Kel'Thuzad sure is a blast from the past hehe, maybe it's good enough in this deck, especially if you don't remove Resurrect.

Later today I'll be trying out a full out Brann Bronzebeard version of the deck, I'll just craft that Elise the Trailblazer, seems to be the best neutral legendary to craft this expansion anyways ;)

The Brann version will ofc include Azure Drake and Onyx Bishop as in the list above, but also Elise the Trailblazer, Kabal Talonpriest, Kabal Courier and Jeweled Scarab (so many good priest 3-drops in wild), maybe I'll incude Curious Glimmerroot as well^^

PS: I've noticed I sometimes have too much AoE and get stuck with a lot of them in hand in certain matchups so I think I will remove Holy Nova, maybe for Chillmaw or Elise the Trailblazer.

Why Piloted Sky Golem and not Cairne Bloodhoof? Cairne seems better and more consistent to me...

Cause they can ignore 4 damage, but not 6 and it's easier to trade up with the Piloted Sky Golem, the difference between 4 damage and 6 damage is huge, I would not recommend running Cairne Bloodhoof at all.

Do you think Justicar Trueheart would be good in this deck? Justicar has great synergy with Raza and can win you the game if you can't draw Reno.

Nah I don't think Justicar Trueheart is worth including, health is very rarely an issue with this deck considering you're running both Amara, Warden of Hope and Reno Jackson.

I'm surprised you didn't include Spiritsinger Umbra as a replacement for Resurrect and/or Onyx Bishop, (which would also make Doomsayer more attractive). I originally thought it was an auto-include in these Quest/N'Zoth decks, but now I'm seeing the more successful Quest decks cut it :(  

Was also wondering whether Brann Bronzebeard would be good as a sort of mid-/late-game power amplifier. Even though there are only 6-7 meaningful battlecries, they're damn strong when they hit. 

Ah yeah you're right I totally should have included both Spiritsinger Umbra and Doomsayer as potential inclusions, great suggestions! :)
Brann Bronzebeard was a consideration, but I felt there weren't enough battlecries in the deck to make him worth including.
Maybe tho if you keep the Onyx Bishop and add in Elise the Trailblazer he might be good often enough. (Maybe you also try to make room for a Kabal Courier then)

I've been running Entomb, Doomsayer and Kabal Songstealer instead of Onyx Bishop, Resurrect and Azure Drake since yesterday and it's working really good, especially Entomb has proven very useful! :)