The part of the game where Rose had to evade dolls of her mother is eerily similar to dealing the Weeping Angels in Doctor Who. In that the dolls can only move, and kill, when unobserved.
Eveline is revealed to be in the hive mind in the mold; despite dying away from it.
The reason Rose snapped at her handler in the epilogue makes more sense after playing through. She's met Eveline and utterly detests the brat.
Ethan is revealed to have lived on in the hive mind; keeping a portion of safe in the form of his old house with Mia and Rose.
Chris is still active with Hound Wolf Sqaud, despite being 65 at the time.