I know more about mafia history than gangster history so I probalby won't name you American street level gangsters who did that but the fundaments and the levels are pretty much the same...
Big Italian and Italian-American crime families (but I could say Russian bratva, Triads, etc... too) were also more like bandits, gangs at the beginning but they reached out to other parts of the economy, into legitimate business and etc... so they could build up their organization... making much more money in the meantime than those ones who stayed street level.
My knowledge on American gangs is lacking compared to crime organizations but if I know it right there are (not Italian-American) American organizations too who are more than just simply street gangs/ornaizations strictly built on illegal money.
I didn't say it's easy to do btw, but that's what Stringer wanted to do, he had ambition to do so but he got played...
I doN't say that he was a good person either cause I don't think he was motivated by saving people from the drug wars with the co-op but simply as much money as possible but he was definitely one of the best characters.
Avon was also one of my favorit characters but he was an oldschool minded guy he lacked that kind of ambition Stinger had. Everyone can decides if that's a good or a bad thing.