How close is the published The Silmarillion to JRRT's Silmarillion?

[Leaf]

Regarding

Originally Posted by TheLostPilgrim

How close would you feel the published Silmarillion is to a version of it that JRRT would've published himself had he lived? Like, percentage wise I guess?

I think the biggest difference between CT´s Silmarillion and a hypothetical version of the Silmarillion made by J.R.R. Tolkien himself would be the frame of the story or the structure of the narrative in general. As it is the structure of the published Silmarillion lacks a history of transmission which is by all means not very tolkienesque. I suppose we all know a great deal about Tolkiens different approaches regarding this subject (Ælfwine etc.). But the question how this allegedly old myths are told seems to be nearly as important as the content of the myths itself. I guess that discussing the various versions of the myths (purely on a contentual level) dismisses this important matter. It´s hard to rate this difference (percentage wise) because it would be substantially distinct from what we´ve got.