Consider:
Act of Authority
Detention Sphere
Alhammaret's Archive
Supreme Verdict
Return to Dust
Chaos Warp
Laboratory Maniac - If I'm getting to draw my whole deck, I'm probably winning anyway
Brand
Forbidding Spirit
One more land or cheap ramp spell
More boardwipes...
Rhystic Study
Nezahal
Shifting Borders
Burnished Hart
Faith's Fetters
Pilgrim's Eye
Kor Cartographer
Auramancer
Overwhelming Splendor
Razor Hippogriff
Hour of Revelation
Hallowed Burial
Final Judgment
Descend Upon the Sinful
Planar Outburst
Rout
Terminus
Open the Vaults
Fractured Identity
Sigil of the Empty Throne
Karmic Justice
Shielded by Faith
Cradle of Vitality
Myth Realized
Disallow
Swords to Plowshares
Noetic Scales
Delaying Shield
Cinder Giant
Path to Exile
Angel of Jubilation - "Combo" with Norn's Annex stopping attacks on me from non-white players

Consider (don't have):
Illusions of Grandeur
Taniwha
Djinn of Infinite Secrets
Crown of Doom
Silent Arbiter
Crawlspace
Delusions of Mediocrity

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Considered cuts:
Goldnight Castigator - Very risky if I don't get to donate it
*** Gwafa Hazid - Don't want to prevent attacking, just prevent attacking me. Also really slow
Divine Reckoning
Elixir of Immortality - Saves me from decking myself, but is that enough?
* Phyrexian Rebirth
Day of Judgment
* Neurok Stealthsuit - Should be Lightning Greaves?

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Cards that are in use in other decks:
The Locust God - Izzet/Bolas
Leyline of Anticipation - Braids

Cards that make no sense without their missing synergy cards:
Goblin Test Pilot - Lacking the untapping auras to go infinite
Grand Architect - Does basically nothing without Pili-Pala
Blue Sun's Zenith - Probably doesn't make sense without the infinite mana from Pili-Pala/Grand Architect

Cuts:
Orzhov Advokist - Probably only stops anything if it doesn't really matter when their dudes are too small or they're attacking someone else anyway, making their threats bigger for when they do want to attack me
Rite of the Raging Storm - Only stops the elementals this creates
Avarice Totem - Chaos, and can steal a relevant thing from a tapped-out opponent, but expensive and unreliable
Volatile Rig, Boompile - Might be too unreliable
Krark's Thumb, Game of Chaos, Ral Zarek, Molten Birth - The thumb doesn't seem worth it without more and stronger coin flip cards, and without the thumb, the low powered coin flip cards aren't worth it
Teferi's Puzzle Box - Chaos, but doesn't really do much...
Whims of the Fates - Chaos, probably slows the game down a fair bit, but otherwise pretty senseless
Celestial Dawn - Mana fixing, but doesn't do anything else, since it can no longer color screw an opponent
Illusory Gains - Chaotic, but can't be donated, and doesn't do anything reliable
Conjured Currency - Can't get back my own stuff, so this is problematic if they steal Zedruu
Nevermore - Does it do enough? Locking out a commander is nice, but it's not very fun
Rest in Peace - I might be discarding to hand size quite a bit, so this isn't necessarily a slam dunk
Fog Bank - Can only block one creatures each combat
Arrest - Only deals with creatures, but does also deal with utility creatures
Lightning Greaves - Don't have enough copies, and the haste isn't all that relevant in this deck, just the protection
Possibility Storm - Adds a fair bit of chaos, and since I do have a lot of redundancy, it might not be too bad for me
Sphinx's Revelation - Should have enough card draw and life gain without this
Keranos - Too slow
Ghirapur Orrery - It's ramp, but not just for me, and I'm never really going to run out of cards
Forced Fruition - Expensive enchantment, and too much value to give other players probably
Vandalblast - I have so much permanent-removal that I probably don't need this
Jeskai Banner - Probably the worst of the mana rocks, and I probably have enough
Library of Leng - No max hand size, and protection from discard, but otherwise low impact
Reins of Power - Can't be used to draw cards with Zedruu, so it's probably just a fog. Possibly a way to win if someone has an overwhelming board, but there are more reliable ways
Lightmine Field - Only really good against tokens, and it stops me from winning with Assemble
Plea for Guidance - A lot of mana. I probably don't need any two specific enchantments that much that I won't get with card draw
Thieves' Auction - Too time-consuming! Besides, there are more reliable ways to get things donated, and more reliable ways to clean up a board
Stasis Snare - Only deals with creatures, but does do so at instant speed with potential for donation
Norn's Annex - 2 life probably isn't enough of a cost unless I'm already in a winning position, so this isn't worth the mana
Hanna, Ship's Navigator - Too slow without boots
Niv-Mizzet, the Firemind - Too much mana
Spellbook - Doesn't do a lot, but could always be donated for cheap card draw with Zedruu