I'm not sure there is a huge correlation between provincial results and international results based on the captain, especially since several players effectively captain a team in any match with injuries / subs / cards taken into account. Not to mention the quality or otherwise of the rest of the provincial team.
I think what is more important is the quality of the leadership group. True, the captain is a big part of that.
There is a lot of flux in the team (and coaches) in recent times, over which the Wallabies have been pretty inconsistent, and I think that impacts more than who is captain.
Eales was a great captain, but he had a great, and very consistent, team around hime with some very experienced generational players. I think any of 4-5 players could have captained that team with good effect given that situation ( and before Phil Clinton loses his rag at some slight against a Queenslander, no, I would not have swapped him for anyone

).
Hence, I think any of the above names I stated earlier would seem to be a decent option, in no particular order.