I was suggesting something similar here. But after looking at all the PADs.
I honestly don't think the separation makes any sense.

A lot of the misunderstanding of approvals may be due to Astarion's character. Wyll may want to kill a bad man out of honor, to save someone, sympathy for someone being wronged.
Astarion - carnage = fun, demonstration of power over the powerful, practical profit.

I don't think spawn changes that much to the world.
It would be too drastic in 4 months. Only to the companions and their opinions.
But Tav can continue to be an evil character and who better than Astarion to support Tav in that? You can choose not to take Astarion to the ritual at all and lie to him that it wasn't that big of a deal. Why should he change from that with 1-2 act behavior.

Astarion is the only evil male companion in the game.

Honestly with approvals it's hard.
For example, in PAD he reacts calmly to Lorroakan. On the contrary interested, the tone is not judgmental. There are tons of PADs where he's the only Evil character. No matter what. Making PADs inactive? Rewriting them is a crime. Adding new ones is a crime, confusing and too sharp a distinction.
For a character like Astarion.

[Linked Image from i.ibb.co]

This is what the author says about Astarion.
"Stephen Rooney argues that two important principles must be presented when creating Astarion. The essence of his character comes down to the value of violence and the dark side of humanity, and his extraordinary charm and allure. This balance is crucial, because a shift to either side would make Astarion extremely unattractive or too one-dimensional and empty a character".

Approval is a meta. It's pretty messy right now. But I don't think it's worth fixing. And it will confuse it even more.

Astarion's author has said that he has left Larian Studios. Only the original author should work with approval. It's directly in character.
Such a suggestion is made to bring some clarity to a character's personality. Now it doesn't make much sense without the author who created the character, if the work is done without his quill - it will still be questionable.

Right now, the best thing that can happen to Astarion's character is he won't be touched.