Vito could have easily ended the Corleones' involvement in all of their criminal businesses by handing over to Tessio and Clemenza and the rest of the Family associates to continue in the rackets.
I reckon this scenario could certainly be helpful to get Mike elected to a major political position

Fredo could have continued learning the casino business, banging cocktail waitresses two at a time!

I'm not sure what happens with Sonny and Carlo though