In regards to BR: I really don't see the problem with the narration as narration. It certainly was not as striking as in Spielberg's A.I. where the narration starts somewhere near the end of the film.
Alan Ladd Jr grew up on noir and had an understanding of the genre. The "awful narration" parroted by so many is a tiresome phrase that needs to be retired. The narration filled backstory that was foundational. Many people hadn't read the novel, so had no frame of reference for it, even if the novel was different. We have the luxury of having had the opportunity to watch it hundreds of times, but if you are watching for the first time, the narration contains background that most audiences wouldn't have. As for the performance of the narration; it could have been corrected at any time, but no one ever bothered.
The greatest weakness of the film is the opening crawl. It is idiotic and confuses the entire story.
A few facts:
•Blade Runner units were created AFTER a bloody offworld Nexus 6 mutiny, but Deckard, a FORMER Blade Runner had no background on the "New" Nexus 6 models.
•Nexus 6s were declared illegal on Earth AFTER the mutiny.
•The new N6s were genetic rather than mechanical, breaking with the previously established robot manufacturing by Tyrell.
•Deckard had been out of a job as a Blade Runner for around 4 years already by the time Bryant recalled him.
•The mutiny took place no earlier than around 2015 nor any later than 2016, around the time of Roy Battys incept date.
The crawl makes no sense in the greater conflict of the story.
A few things people routinely miss:
Despite having been manufactured on Earth, no one on Earth seemed to know what the finished product looked like except Tyrell, who recognized Batty by sight: -One individual model from hundreds of individuals in production. Tyrell very much knew exactly what was going on.
Unlike, the N5s, the V/K test did not work so well on the N6s, which almost got Holden killed.
There is never any mention of who (or what) is being fought. All the fighting near the colonies is not explained.