Playing along with the assumption the Vito could have survived somehow in Sicily, he would have attempted revenge anyway; loosing your father, brother, and in full view his mother, scared Vito... that's why he went after FANUCCI (The Black Hand). Think about it; Vito was a peaceful grocery boy working to get his wife a single pear, the Black Hand took his job at first, pushed him into non-violent crime, then he came after him at that too! The "Bad Don" syndrome was happening all over again.

Has anyone ever asked why young Vito took the decision of killing Fanicci so easily despite the urges of his more experienced partners Tessio and Clemenza, who wanted to pay the man?
He did not display a violent streak before that point, so why did it come up now, and not in a life or death situation, but in a money issue, where everyone accepted paying as a fact of life? In my opinion it is because Fanucci (A Bad Don), reminded him of Ciccio (another Bad Don).

Furthermore, from this experience, Vito has grown into a "Good Don", good and bad here being relative terms - you never see him do the nasty things these guys did, and was always proud of the fact that he is "A REASONABLE MAN"!

So back to the question; keeping the above in mind, Ciccio would have continued hunting Vito, and had Vito been given a chance to grow up, he would have definitely killed Ciccio, and became a Don (Just like he killed Fanucci and became a Don)