Why, they were lacking scoring? They played too much defense? Did they pass too often?
The biggest problem I see is that they continue to go with youth, while at the same time picking players who haven't ever won anything. How many playoff series have LeBron, Melo or Chris Paul won? You can't win when you build your team around seven different guys, all scorers.
They should stop picking the best players, and just pick the best team. Why not just take the entire Miami Heat or Detroit Pistons team? Many of the international teams are filled with players who play with each other all year round.
For once, take a team of veterans who have experience playing in higher competition. Find some guys who have played together and have won together, and build around that. How about a roster like this:
C - Brad Miller
PF - Udonis Haslem
SF - Tayshaun Prince
SG - Dwayne Wade
PG - Sam Cassell
Bench
Posey, Payton, Mourning, McDyess, Lindsay Hunter, Bowen, Brent Barry
That seems like a team that would have more defined roles and help a coach matchup against any international team. You still have scorers, but you have some other guys who provide defense, rebounding and leadership.