Six months and many personnel moves later, the premise of this thread still rings true.
The Seth Currys and Danny Greens of the world function as complementary players on a championship team only when the players they're complementing are truly elite drivers of championship-caliber play -- LeBron and Anthony Davis caliber players for example.
As of now there is no evidence that Ben Simmons and Joel Embiid fit that bill. Until those two players take the court with the maturity, passion, and leadership of the elite players in the league, the supposedly complementary pieces assembled around them won't matter.
The future of this team revolves around whether Doc Rivers can leverage greater maturity and leadership out of Ben Simmons and Joel Embiid.
We'll know within 10 games next season whether there has been any change in the character of this team as a function of Rivers's influence on Simmons and Embiid. Last year it was evident within the first 10 games that Brett Brown hadn't done it. If Rivers can't do it either, the question becomes whether Simmons and Embiid have it in them at all.