Your approach is very interesting. You interact with the language actively like for example shadowing or writing important words and phrases. I will try this approach.
This third medium narrators voice is like a barrier between my subsconcious mind and the target language text. Perhaps I should read the whole book in the first place then I should do L-R of the same book.
It is not the difficulty of the book that is problematic per se even with short texts/short lessons if I do L-R even without reading them in advance I have a problem understanding the text. Once I have read the text beforehand, I can do L-R easily with 100% understanding (but again I have done this with short lessons, I am not sure about novels).