I think unfrotunately we will be stuck with Rocky as captain until after the RWC. While he may be getting better, his ref management, decision making and general leadership all are quite deficient. I very rarely see him in the ref's ear, pointing out continued opposition infringements at the breakdown, illegal opposition scrum techniques, etc. and when he does it is often very late and kind of looks like he's having a whinge - kind of similar to how I think Hoiles seems to deal with the refs.
In terms of his general leadership, I think he is the type of captain who tries to lead by example. But unfortunately he's a little too inconsistent for this and doesn't seem to have to many ways of getting his team to lift when they are not travelling well. In constrast, it always seems to be Pocock and Sharpie giving the team a gee up or bringing them into a huddle for a regroup and possibly suggesting a change of tactics.
For mine the Wallabies captain should either be Sharpe or Pocock. Both players handle themselves as highly as anyone else I can think of in international rugby both on and off the field, perform at an outstanding level consistently, are well spoken and can handle the referee with a suitable amount of respect (although in Pocock's case I'm just guessing this would be the case) and also have the full respect of their teammates. I think Pocock would be more than capable of handling the extra pressure, but Sharpie would probably be the better bet for the world cup with Pocock to take over after his retirement. Sharpie's ref management is excellent as displayed at the Force, where his leadership has also been outstanding (especially through the rather difficult last season).
Note: I may be a little biased towards the Force, but I don't think there are really any other captain candidates in the wallabies. Genia doesn't seem to have great ref management skills either, and tends to get subbed off in most games.