Kevvie needs to bring in some old heads, leaders on the training track hopefully and I do think this is one area Macca helps out by coming back. He also needs to put up a teamsheet with no names on it and say boys, every position is open, you show you me you want to be on it, I don't care your name, your past or your standing in the game.
Kevvie's assistants also need to instill some kind of structure in both attack and defense, that is a priority from week 2 after players in different positions have been identified. The Broncos have (and always will have) guys who can score a try from nothing but that should be the icing on the cake, not the icing on a pile of a poo.