Suprised that neither Stoinis nor Maxwell is in the team. Even Mitchell Marsh or somebody like a Travis Head would have been a good edition instead of Turner.
The issue with Australia is that all of their good batsmen, even the aggressive ones are naturally top order players or openers in white ball cricket. The most flexible ones are inevitably shunted down the order like Head and Smith at four, Handscomb at five, Carey at seven. This is even worse in the BBL where Burns for example bats at five for the Heat.
The only exceptions who are actually middle order players that I have seen are Mitch Marsh and Turner himself. On paper, Turner has all of the attributes to thrive. He is one of the quickest between the wickets, can bowl part-time, can slog. Due to fitness and form, none of these are unfortunately being shown by him right now. Like @Jalen mentioned, I would go with Marsh at five or six with Carey as his partner for the moment.
As for seven, the Australian Board overrate Agar's batting for some reason but he is one of the few decent spinners they have at the moment. Him at seven means the Aussies can play three quicks with Zampa and still afford to finish their full quota on most days. The previous era of relying on Stoinis/Maxi/Finch/Smith for ten overs was quite terrible and left the Aussies weakening their actual strength to cover up a weakness.
While Stoinis and Maxwell have been very impressive in the BBL, it is important to remember that it is in a completely different format where both of them play in the top three. Also, with all due respect the BBL has noticeably dropped off in quality over the last couple of seasons. Maxwell was quite poor in the Marsh Cup where even Sutherland actually outshone him despite batting behind him. Stoinis for all of his muscle doesn't really rotate the strike well and is a bit one dimensional in his aggressive strokeplay too.