Baron Helmut Zemo - upgrade from bracket 3 to 4

I’m trying to push my [[Baron Helmut Zemo]] mono-black Commander deck from Bracket 3 into Bracket 4 and would love advice on how to sharpen it.

Right now it’s mostly graveyard setup + reanimation: fill the yard with cards like [[Entomb]], [[Buried Alive]], [[Unmarked Grave]], [[Stitcher’s Supplier]], [[Mesmeric Orb]], [[Stinkweed Imp]], and [[Golgari Thug]], then cheat creatures out with [[Reanimate]], [[Animate Dead]], [[Agadeem’s Awakening]], [[Breach the Multiverse]], and [[Rise of the Dark Realms]].

For Bracket 4, I’m thinking the deck should move away from slower value reanimator and become more of a fast mono-black combo/reanimator-control shell. Cards like [[K’rrik, Son of Yawgmoth]], [[Bolas’s Citadel]], [[Peer into the Abyss]], [[Vilis, Broker of Blood]], [[Hoarding Broodlord]], [[Gray Merchant of Asphodel]], [[Bloodletter of Aclazotz]], [[Syr Konrad, the Grim]], plus the big mana package of [[Cabal Coffers]], [[Urborg, Tomb of Yawgmoth]], [[Nykthos, Shrine to Nyx]], [[Crypt Ghast]], [[Bubbling Muck]], [[Dark Ritual]], [[Cabal Ritual]], and [[Songs of the Damned]] already make it feel like the deck wants to win explosively.

What upgrades/cuts would make this more clearly Bracket 4? Should I lean harder into [[K’rrik, Son of Yawgmoth]] / [[Bolas’s Citadel]] storm, [[Gray Merchant of Asphodel]] drain lines, or just make the reanimation package leaner and faster?

Decklist: https://mythichub.com/decks/3d501581-d984-4f1f-a79d-580c0229729a?mh_share=copy_link