My first thought was a different Rebecca....Rebecca Ryker, aka Death Locket. She had ties to some of the Avengers Academy students, and she had some scarring on her face (around where her implants were). The "important possessions" she wants to get back could be her cybernetic implants and weapons. And if she's inherited any of her father's technical genius, she could potentially fit in with the Future Foundation kids.
I just wasn't sure how this would mesh with Death Locket's recent appearance in the JOURNEY INTO MYSTERY mini that was a WOTR tie-in. So maybe it is Rikki after all.