captainsolo said:

I honestly think it improves on the original film's story to such a degree that the entire meaning changes.

That's why I have such a problem with it.

A major theme of the film - one of the reasons I love it so much - is that the replicants, the individuals who are not human, turn out to be much more human than Deckard, the human whose job it is to hunt them down. (That's part of why I like the "I'm sorry, Sebastian" line - it humanizes Roy a bit, which is part of the point of the movie.)

This also makes the Tyrell Corp.'s slogan more relevant and chilling - "More human than human." It's true - Batty, an artificially-created being, is more human than Deckard, a human.

But all of that gets thrown out the window if Deckard's a replicant, too. It destroys one of the core themes of the film, one of the themes I latched onto so strongly.