7 discard spells seems excessive for a deck trying to pressurise the opponent on the board. I would go to 4 Inquisition of Kozilek (with 2 Thoughtseize sideboard). Or 4 IoK and 2 TS main

I like Go for the Throat over Dismember in mainboard as easier to cast given you want for Spectral Procession and for any targets it can't hit you use Path to Exile

I would drop an Isolated Chapel - running 4 is excessive in any deck in Modern. I would also replace one Godless Shrine with a swamp. You only need 3 shocks given you have many ways to tutor for it. I think 22 lands is ok with this deck.

6 or 7 discard spells is fine. Go for the throat always requires 2 Mana, and doesn't hit anything of affinity nor wurmcoils. Dismember costs more life, but is much more versatile. I'll agree on chapel, but only if he runs more fetches. Absolutely no to replacing godless for a swamp. You need to have access to 3 white Mana on turn 3 for spectral. 23 lands is necessary, I've considered going to 24.

6 to 7 hand disruption is what you need to run a successful b/w tokens deck.

Dismember >> Go for the Throat. Don't need black mana to cast Dismember btw.

4 Godless Shrine is a must.

Wurmcoil Engine is not commonly played, what % of decks play that? And you can just Path to Exile it. And Affinity has problems with Lingering Souls and Spectral Procession and Zealous Persecution. So I say Go for the Throat better than Dismember in the mainboard. You ideally don't want to pay life for Dismember, and if you are trying to hit for Spectral Procession then for it is a stretch. Go for the Throat is just more efficient given that Path mops up the other threats

On the mana, yeah 23 lands is probably right.

Discard - happy with 6 but 7 is over the top

Tron plays it, and it is gaining in popularity. The life loss from dismember is well worth the added versatility it brings. A one Mana removal spell is much more useful, even if it does cost life. and 7 is not over the top. Hand disruption is how b/w tokens is able to be a viable deck in modern.

I've thought about it before, but it just isn't worth having a dead piece of removal in hand.

Clawed6, paying 2-4 life for Dismember is no big deal. With cards like Sorin, Solemn Visitor and Vault of the Archangel in the deck, it is easy to make that up.

The reason 6-7 hand disruption spells is necessary in this build is because you generally won't start building your board state until turn 3. Therefore, you need hand disruption to slow down your opponent so you do not fall behind early. Hand disruption and 1 mana removal spells, this is how you win with b/w tokens.