My first question is this: Wait, did you just have a Rishadan Port lying around? Holy crap! I think your wincon is for sure going to be Teysa most of the time, so you need a way to protect her. Lightning Greaves or Swiftfoot Boots will be great here, and if you want you can add more offensive equipments like Loxodon Warhammer or Sword of Vengeance. What’s awesome about Teysa is that she’s innately unblockable so you can focus on simply giving her hexproof/shroud and a nice power boost. Vigilance on her is pretty spectacular too. With Teysa pretty much self-sustaining, you can focus on another worth goal: not losing. White/Black gives you access to some of the best token producers and board controlling cards around. Making lots of tokens, then sacrificing them to Phyrexian Altar or Ashnod’s Altar to ramp into a big spell while clearing the board with a Grave Pact effect seems pretty solid to me.

Cards that might be cool to include: Vish Kal, Blood Arbiter; Trading Post; Mikaeus, the Unhallowed; Mikaues, the Lunarch; Unburial Rites; Dread Return; Requiem Angel; Ashnod’s or Phyrexian Altar; Grave Pact; Martyr’s Bond; Debt to the Deathless; Wrath of God or Damnation or Day of Judgment; Attrition; Bonehoard; Lashwrithe; Marshal’s Anthem

Angel of Glory’s Rise might be really good in here if you push Humans as a subtheme a little bit further. Also keep in mind that some of your humans like Cackling Witch are errataed to be human but don’t say so on the physical card. As it stands though, I’m not sure Angel of Glory’s Rise is quite worth the inclusion (though easily could be with some work- maybe try a card like Conspiracy).

The Bogbrew Witch/Festering Newt/Bubbling Cauldron cycle I’m not entirely sold on. Unless you get some sort of crazy recursion or cloning effect going on, Festering Newt won’t do too much, Bogbrew Witch only works twice, and Bubbling Cauldron doesn’t do enough to warrant the other pieces.

I feel the same about Cackling Witch as I did Angel of Glory’s Rise- really cool card that could use a bit more support. With black, you’ve got lots of cards that care about being in the graveyard (or ways to recur them). Stuff like Valor or Obzedat’s Aid might be cool to think about too. Also look into cards with Madness.

Devout Harpist will probably be pretty dead a lot of the time. It’ll be great against certain decks (Uril or Zur) but totally dead against most others.

Twisted Abomination feels sort of weak; it’s a great wall but you’ll probably be better off with something like Bloodghast or Reassembling Skeleton.

There are tons of ways to abuse Vizkopa Guildmage. Defintely keep and add some more support. Sanguine Bond and Exquisite Blood are what I’m picturing.

Afterlife/Doom Blade/Expunge/Murder/Reckless Spite/Reprisal/Riot Control/Scent of Nightshade/Spiritualize/Festival of Trokin/Path of Peace/Sever Soul/Pacifism/Oblivion Ring/Hobble/: One thing I learned pretty quickly in EDH is that one for one removal spells, while not bad by any means, can be tough to justify in this format. I always find myself holding onto to them for way too long, and once they’re gone it feels weak. I try to stick with cards that either have flashback or a really large effect, or I look for other ways to repeat their effect with an Enchantment or even Isochron Scepter.

Nightmare Leash seems like a worse Lashwrithe to me. Combo either with Urborg, Tomb of Yawgmoth and your Teysa can probably one shot someone.

Castle probably doesn’t do enough unless you can easily and consistently give everyone Vigilance. Marshal’s Anthem or Glorious Anthem will be better, I think. Mask of Law and Grace will probably also be better off as something that pumps up Teysa- if you want to splurge on a card, pick one of the enemy colored swords like Feast and Famine or War and Peace. Sword of Light and Shadow might actually be your best bet, but could get awkward if you want to enchant Teysa with something like Soul Link or Spirit Link.

Maybeboard stuff you list:

I would definitely stay away from Ankh of Mishra. It’ll draw a ton of hate and end up hurting you.

If you find yourself needing ramp, Bog Witch might be pretty cool. Keep this in mind if you find yourself wanting to support Cackling Witch more too.

Corrupt will also be awesome if you decide to put Urborg, Tomb of Yawgmoth in. I think it might be worth including now anyways.

I really like Dauthi Embrace, but I think it will depend on how you want to win. Teysa won’t ever need it.

Fodder Cannon probably won’t deal enough damage to many creatures in the format.

Horn of Greed is sort of the opposite of Ankh of Mishra- it’s very group hug focused, and a lot of decks will be able to use it better than you can, which puts you at a disadvantage.

Outbreak is very situational and not quite powerful enough.

The Red Scarab cycle probably isn’t worth including either; it’s too reliant on other decks and you want things that will be good in many situations.

Crypt Incursion will be great against lots of decks in the format. Keep this in the maybe list.

Darien, King of Kjeldor can be insane for you.

Blood Artist is good but personally I prefer Falkenrath Noble. The flying is surprisingly relevant and the somewhat larger body is nice. He can’t just get Staff of Nin’d. Both might not be a bad idea though.

Harvester of Souls is fantastic, definitely put in!

Grave Betrayal can be hit or miss. If you get a good enough Grave Pact engine going, it could be really good though.

Yes yes yes to Debtor’s Knell, holy shit.

Farrel's Mantel on Teysa seems like it would be pretty neat. she always gets through... so i can decide to hit any creature on the board with at least 6 damage + she has vigilance...