Also, I would have liked it better if they were insistent on having a brother for Data, that they used Lore. I mean we know he was deactivated, but it was never stated his body was destroyed. Lore's body could have been covertly stolen by the Romulans with the intent to replace Data, instead of a clone to replace Picard. Maybe "B4" could have been revealed to be Lore, playing dumb or just reprogrammed by the Romulans which caused the slowness...but with Data's memory download, it changed Lore, finally over-ridding his narcissistic impulses, and where through Data's death, he finally is redeemed?
I have long championed the idea of having Lore in "Nemesis." It would surely have been better than what we got. Data's entire story arc for "Nemesis" is nothing but contrived, from the discovery of ANOTHER Soong android to his poorly conceived death scene. Throw out B-4, Shinzon and the Remans entirely, and instead focus on the Romulans and Lore. The only thing I can't reconcile is how to explain the hostility of the Romulans, who seemed on good terms with Starfleet as of the end of Deep Space Nine a couple of years earlier. Would it be a rogue group (as presented in "Nemesis") who reactivate Lore, or are these villainous cousins of Vulcans working on orders from the Praetor, himself?