Add  Sphere of Resistance?Thorn of Amythyest? It'll help slow the game down more. Trinisphere isn't enough in my honest opinion.

I'd have to agree with Anusien. Razia, Baros Archangel is better than Spirit of the Night. 11 Creatures in the deck is too much. I ran only 3 creatures in my oath deck. Akroma, Angel of Wrath, Razia, Baros Archangel, and Simic Skyswallower. I usually hate Oath into Swallower first round of milling the deck.

My friend had a similiar deck.  Ran Living Dead as his alternate win condition.

I'm an ichorid player myself so I can deal with most of the stuff people sb against it. The only viable deck I see ichorid having a problem against is Stax and Flash. But all  ichorid deck should main Cabal Therapy, Leyline of the Void and Chalice of the Void. Leyline helps against Flash and stax. Unless the person is smart enough to run Chain of Vapors but you are right about there's no perfect Ichorid deck. I main Dryad Arbor, Serum Powder. I've only seen 2 versions of Ichorid. One Abusing Serum Powder for a bazaar for the abuse of using Dragon's Breath and Sultured Ghoul with Dredge Return. The other one using Flame-Kin Zealot.

Leyline of the Void is easy to take care of with Reverent Silence Simplify Ray of Revelation
Pithing Needle Oxidize will take care of this.
Extirpate I'm not going to argue with you on this one. Who's going to SB 4 Extirpates against Ichorid? IMHO(In my honest opinion) it's a waste of space in your sb. You'll have to Extirpate the main spells in the graveyard which is Dredge Return and Bridge from Below I think... Echoing Truth a better SB against Ichorid. I mean who cares they have X amount of tokens.
Tormod's Crypt I smell Chalice of the Void for 0
Yixlid Jailer is just a measely 2/1 that can be taken care of with Contagion