The example you used shows one difference between Vito and Michael. Coercing the bandleader was a simple, personal favor Vito did for Johnny. Setting up Geary was a bigger deal--Michael was angling to avoid a big financial penalty ($250k plus 5% of the gross of all his hotels) payable to Geary. On one hand, Michael's method was justified by the stakes involved. On the other, it's an example of how he was constantly overreaching--and having to deal with the consequences.