Fot me, Cadden's best role as it stands is when he has a bit of a start to run at players at pace, and has some support to either play the ball off, or overlap. Its when be has to do it from a standing start and rely on close skill to get round a player he struggles. That's not a slight on him- just the way it is I think. Similar to when Pearson broke in I think...he was so much better travelling at pace.
So, wether it's right back himself, or right mid with a good attacking right back behind him, or even right wing back bit with decent tehnical support from midfield...all I think could work. But right back thus far seems the best bet as it gives him a wee bit more time to do things and get motoring. Expecting Cadden to do it all on his own as a wing back or winger just isn't going to work until the technical ability improves.