Ive said this a few times and still think its true. Good wingers or midfielders are usually technically better than a full back. We have seen the likes of Milner Young Delph all become solid in that position and all technically good. So i think Bailey could become a world class full back. Imagine how good Traore would be. Even Trezigue could be pretty good there. Even Elgazi.

Martinez
Traore Konza Mings Bailey
Louis McGinn
Buender Ings Watkins