> Even the idea that they would make a replicant hunter that's weaker than the "basic pleasure model" it's designed to hunt doesn't work.

I don't disagree with your points, but one explanation is that Deckard was made for the purpose of passing as human and had to be kept ignorant that he was a replicant as that would likely affect his job performance. If he was made stronger than other people, then it would have tipped him off as to his nature.

That does then raise the question of why Tyrell would present Rachael as being his most "human" creation unless he was testing/playing with Deckard to see what happens when replicants start to replicate.