Before I answer the OP's query, I will throw some qualifications out. I am answering the assumption based on a team full of 3* players with high character vs a team of 5* players with low character. And by character, I mean high level of ethics and morality, dedication not only to their sport but to their team and to winning.
I would take the team of 3*, high character players. This is because I don't believe there isn't a huge difference physically between 3* and 5* (yes significant, but not huge). And I believe that over the long run, the low character 5* will be a cancer to themselves. They will get in trouble, make mental mistakes on and off the field, fight among each other, and ultimately the lack of dedication to the team and winning will more than make up for their faster 40 time and vertical.
And just to speak to the whole Iverson topic, I'll say this. I've always been a huge Sixer fan. Even through the Shawn Bradley experiment. Until Iverson. I'm still trying to recover my passion for the Sixers. I just could not get myself to pull for him. Yes he was talented. But he was a piss poor teammate. His dedication to the concept of winning as a team was just not there (or he'd have realized the value of practicing as a team - yeah, I'm talkin bout practice).