This is only a constructive criticism, of course. In my humble opinion tales like The Lost Road, Tar Elmar, or The New Shadow (this one also possibly never would be in the "original" Tfte), are very individual and very very unfinished to be in any place of these projects.
As for the structure, without any pretentious for my part, do you consider in some time my structure?. For me, that already read it is, even cronologically, very accurate, and very "Tolkienist".
Every chapter you quote is merged into the narrative.
Greetings