>>3566558>>3566564(contd again)
So why is it poorly written?
When Rei Q is established to be a clone in a series, you've already established the quintessential part of identity - it's a different person.
This is because a clone is simply a genetically identical organism, and no one would claim two twins are the same person or have equal identity. So Tsurumaki has shot himself in the foot from the get-go, and ruined the originals premise that could work to explore identity.
There is no possible way Rei Q's exploration of herself to be another person would ever matter, because the answer to the question was already given: she's her own person.
That brings up another question:
Why on earth would Rei Q think she is Rei? Why would she have problems being her own person, or just follow orders? This was never established. In other words, the source of Rei Q's conflict doesn't exist, and therefore Rei Q is simply cliches being played out. To great effect, because Rei Q is easily the heartbreaker of the final film.
Contrast this with Rei Ayanami from NGE, or even 1.0/2.0 before the plot goes sour. Rei is conflicted about her identity because she knows she's been revived ones. Her interpersonal relationships, i.e rejecting Gendo and accepting Shinji's kindness, is a conflict because Rei actually cares about Gendo initially. This because Gendo, being a real person in NGE, actually worried about Rei and made actual effort to ensure she was safe.
But for Rei Q, there's no such thing. You can't actually explore anything of depth, and so you've got Rei Q looking at cats. Which is adorable.
In the end, Rei Q is also absorbed back into the "greater Rei" that apparently exists outside the entire story, on that stage set.