In the books, Lady Stoneheart is a resurrected Catelyn Stark, whose sole purpose is avenging her family. Maybe Arya the assassin is the closest thing we'll get to Lady Stoneheart, or maybe Mom will rejoin her on her quest.
Gilly has had a rough life, and we'd love to see her as the lady of her own castle. The path to the head of House Tarly is pretty clear now, given that Samwell's disapproving dad was burned by Drogon for refusing to bend the knee to Daenerys.
Gendry is the fastest Baratheon on two legs. He's also the only Baratheon left alive, but he's really, really fast. He covered the distance from the wights to Eastwatch in just one scene. How much ground could he cover wearing fewer layers?
We have to get at least one more sneaky-faced Arya attack before the series is over. Our dream: Arya hijacks Jaime's face to get close to Cersei, satisfying the "little sibling" prophecy and avenging her father's death.