The coaches want JNR to be more offensive because his tendency or fixation has always been to sweat the man and chase and tackle rather than getting the ball himself.
Of those NT games you refer to, I watched a few of those games and except for the commentators obsessive search to call the Rioli name he never dominated a game or got many possessions, had a highlight goal here and there which was enough to put him up in lights, (he never kicked a bag), because he was Mr Magic's son.
I also watched several of his games live when playing for Scotch where they tried him both mid and forward, i were reporting even then that i was disappointed that he sweated the man and not the ball and while people on PRE were asking for us to trade away our 1st pick so we could get points to draft him i were saying he was more likely rookie material, (but that was never going to happen because of who he was).
So what is the player he is or the player he is not?
**This is what I would do in the VFL even to the detriment of wins there, play him midfield and fixate on the ball, tackles and chasing are already natural to him.