That's a pretty sizeable gap above, you might want to trim it up.
My main concern is this;
Why would you play Sui Black(or any variant) WITHOUT 4 copies of Leyline of the Void maindeck?? It isn't
bad against any deck, and it can simply steal some wins for you vs. quite a few of the decks out there. First turn LL and Duress/Seize is pretty much a win vs. Flash. Most Ichorid decks have no chance at recovery(few run Chain in the main). And yes, LL is good vs. Stax. It neuters Welder and Crucible while severely compromising Bazaar and Smokestack. Bomberman? You betcha. Psychatog? Sure. YawgWill? Of course. Did I mention that if it is in your opening hand it is uncounterable? and free? If it isn't in your opening hand you can still hardcast it(turn 2 with a Ritual).
Im not sure adding Confidant and taking out Unmask is the correct play. Unmask's alternate CC allows me to play a critter and still disrupt BUT it doesnt combine well with Dark COnfidant
Dark Confidant is the very first creature that should go in this kind of deck. Unmask is just too rough a trade at 2-for-1. The small chance it could be Misdirected makes that even worse.
I would keep Demonic Tutor in the deck. At worst it can turn 2 mana into 3 by fetching Black Lotus. At best it can save your ass by fetching disruption.
Demonic Consultation is good with so many 4-of's. It's instant speed, and besides, you weren't planning on using all 60 of your cards anyways, were you?
I usually prefer Edicts in the maindeck over Darkblast, but it depends on your meta.
I also agree that Carnophage is an inferior creature. Not that Sarcomancy is great, but at least it creates 2 permanents and doesn't make you take damage for using it to attack.
If your meta is becoming creature light, a first turn Negator(via Ritual) complemented with a CotV@0 or LL is a pretty good start. But then again, you could easily add in a few Bayou's and put in 'Goyf and not take away the 'essence' of Sui Black. Green gives you MANY anti-artifact and anti-enchantment options in the SB. It's worth looking into. Ok to help the cause, I'm make a quick B/G deck.
Born on the Bayou
Critters: 16
4 Dark Confidant
4 Tarmogoyf
4 Oona's Prowler
4 Hypnotic Specter
Spells and such: 18
4 Leyline of the Void
4 Hymn
4 Duress
2 Thoughtseize(or 1 Consultation and +1 Edict)
1 Demonic Tutor
3 Edict
Lands+Mana: 26
4 Bayou
3 Bloodstained Mire
3 Polluted Delta
8 Swamp
1 Stripmine
2 Mox
1 Black Lotus
4 Dark Ritual
SB:15
Whaterver you want: Naturalize, Oxidize, Seal of Primordium, etc. etc..
I like Nantuko Shade and all, but he's pretty worthless when he has a twin unless you are vs. aggro.
I thought about Chalice but went for Hymn since the list currently has Rituals.
I just made that up, so feel free to change anything. Go ahead and add in Wastelands if needed. If Hippy's were taken out, you might not even need the Rituals(dare I say such a thing???) Vials and maybe Clamps could be added too, who knows? Just keep Goyf in there, he's the best aggro creature you are gonna get. Or not, and just stick with mono-black.
Good luck and I hope some of that helps,
Mike