Some characters are good at getting a special place in the heart.
Ironically, that's kind of how I feel about Katherine. Her broken bird-ness has cut deep into my soul, and now I just want to give her headpats and teach her to be happy via the healing power of love. Which I totally did
not anticipate when she first showed up.
I actually don't want Ellie to begin to talk. I love how expressive she is without the need to talk.
I feel like the natural conclusion to her arc is talking, though. ie, she stopped talking because of feelings of abandonment etc, so reestablishing the relationship fully and healing old wounds (and overcoming all the "bad memories") would ultimately end with her becoming verbal again.
It's always possible that she'll retain a lot of the non-verbal expression she developed during her time not talking, but I feel like it's almost inevitable that healing the rift in her relationship with her mother almost has to end with them starting to speak with each other again.
I originally assumed that Rachel's story was meant and the respective people confused Sequel with Prequel.
I'm pretty sure the sequel comment was always meant as a joke. Essentially, version bantering won't even stop when the game is completed, but will continue on until after a hypothetical sequel is completed.