You question seems to have a basic tenet of the JW's built into it as an a priori assumption
JW's and kindred groups believe the sixty-six book compilation is a single, contiguous work with a central theme and internal continuity from cover to cover.
(As opposed to a loosely organized anthology reflecting a number of theological views which did not truly reach its final form until the Middle Ages.)
I'm really not sure how some of the doctrines you mention above could be judged as scriptural or unscriptural in the absence of this view.
I'm willing to don that cap sometimes for the sake of discussion with a believing JW, but I'm a little puzzled here, since you're not.