Likely identity of new Spartan?

I have formed a speculation of who the new spartan is in Halo 5. It could possibly be the focus character in Ridley Scott’s project Marlo. Talked about here: http://www.youtube.com/watch?v=rPBkBqMaQUo This would be a likely candidate in my opinion. As the views of this character could make for an interesting take in the narrative and that they said that the tv/movie projects will expand on the universe in the games too. Alternatively I believe the Character could be Thorne. While Thorne is not a new character, he is new to the campaign. And will probably be seen as new to many who haven’t played spartan ops. Tell me what you guys think. Do you think either are likely to be the new character? Personally I’d go with my first speculation with the Marlo character.