I agree that Conca hasn't shown much yet but he has only played three games and been given big defensive responsibilities very early. I keep going back to highlights package I saw of the kid and the talk of his tremendous leadership skills. I think, much like most early draft picks, his natural game is based on skill and attack not on defense. In fact if young players are too defensive then they do not stand out and are not picked up so young players are rarely rewarded for this aspect of their game.
I think Conca would shine more if he was placed on the wing or as a rotating midfielder but Dimma is looking long term for his development not immediate. He is fufilling an important role for the team also something you would rarely give to a new recruit.
I think the backline will not be in his long term future. He was recuited as a midfielder not a backman like Batchelor. What he is gaining is a wonderful education extremely early which recruits rarely if ever have the luxury of gaining. His stint in the backline forces him to mold his defensive side of his game where, if he was moved directly into the midfield, he may have gone into automatic pilot and played his normal attacking game regardless of the coaches directions.
Big ask of a young fellow but probably a big reason he doesn't seem to have 'shined' to date.
Just my opinion of course....