That's what my read used to be, and I'm still now convinced that it is wrong. Your second sentence is certainly how he sees himself, but he's not really doing anything new there -he has a front, he's trying to get away from the street and be a wholesaler, get into the real estate game. There are other players who did that successfully that are referred to by the other characters - I think Butchie has a few lines about a major player from way back when whose name you've never heard of who did that.
Stringer didn't even really succeed with rebranding his weak product and he didn't come up with the coop - that was Joe. Joe was the real brains, and the real leader of the coop. And Stringer didn't fail because he was applying the street rules to the politics - he died because he stopped abiding the street rules. Even trying to hit Clay Davis, which would have caused his fall, wasn't an application of street rules. It was him once again falling prey to his ego and trying to go after someone uninvolved in the game because his pride got hurt.
Avon turned on Stringer, but Stringer was already going to get got, and deservedly. It wouldn't have served Avon at all to protect Stringer, and by the rules of the game he had it coming anyways. Avon could see that Stringer was way out of pocket all over the place and couldn't protect him, couldn't keep him from fucking up.
Avon is actually the one who might have held on for longer if he hadn't been betrayed by Stringer - Marlo was more fierce and more cunning than Avon, but Avon still had more muscle and he had a location on Marlo. If they had managed to hit Marlo at the rim shop that night, that would have been it for Marlo. But Stringer took down the whole fucking organization.
And in the end, even smart businessman Joe doesn't win against ruthless soldier Marlo. And Marlo will eventually lose the crown, and it'll be some newer fiercer quicker Marlo that catches him slipping.