I liked his preposal, including the vrock one at the end.
As for only life and light deities offering turn undead, I disagree. All clerics can turn undead because its not tied to the gods domains or portoflios, its tied to the spiritual essence that makes up the Gods bodies which is more universal. The difference between holy and unholy energy is frequency and purity, its all spirit.
See the way I see it a God is different then a mortal. A mortal's spirit is its animating force, tied to its soul. In a God its still the animating force, but it is much more powerful then that, its also the Gods flesh, its "biology" and basic divinity. Healing and Turning Undead and cleric spells draw from this part of a God
Where as a Gods' Dominions/portofilios are a God's jobs only tied so much more to a God then mortal's job could be, that they combine to form the God's soul. Its why Gods can never be permantly destroyed as long as thier domains still exsist its allows possible to bring them back.
See that's why I see Cleric's being more generic then Priests. Clerics draw on the body and will of a God, but at the end of the day flesh is just flesh no matter where it comes from, although some may be healthy and some diseased.
A Priest on the other hand draws straight from a Gods soul, more intimate, and more diverse and unique although they might need to draw some spiritual essence with it to allow it to physically manifest.
A Paladin draws power from virtues and vices which are group minds from all creatures with minds including gods so every god is apart of every vice and virtue. In essence the Paladin draws power from a pacticular facet of a gods via the virtue/vice, which colours the Paladin's enactions with that God. Think the First Evil from Buffy and how it could take the form of the Hell God Glory, because all evil that is done including that of Gods is apart of it.
That's just how I picture it. My essay on D&D theology

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