Re Varys mentioned above.. That conversation with Melisandre referenced " this LAND" not ISLAND, that is, Westeros, not simply Dragonstone.
So he and she will both die in Westeros at some point.
Feel I have to defend my girl Arya. Yes, she has become a bad ass killer, but because of everything she has seen/that has happened to her.
She has a true sense of what is fair, or right. Even as a trainee Faceless Man, she wouldn't kill Lady Crane, even knowing that it would mean she herself was in danger.
She has learnt that no one can protect or save her, so she has to do it herself. Her father was beheaded before her eyes, she saw the aftermath of the Red Wedding, with Robb's headless body being ridiculed. She got to the Vale just in time to hear that her aunt, another potential protector, had died. I loved that moment where she burst out laughing.
My theory with her and the Hound is this, she refused to kill him when she could have done. I am really looking forward to her reunion with him. I loved that moment in S7E7 when he and Brienne were talking fondly and ruefully about her, how she has grown to not need their protection.
Her soft spot is of course Jon. Out of all the true born Starks, she loved Jon the most. She will be VERY wary of Dany!