Ricardo,

I'm going to try (from now on) not to be so critical. This is your baby, you call the shots. We can all appreciate the fact that you are actively soliciting feedback and criticism, so 'big ups' to you for that. So instead of attack mode, I will switch to idea mode. Here are two things you may want to think about and use for your Vincent angle...

A: There has to be an opening party of some magnitude. Vincent getting married, perhaps?
Or, depending on when you start the Vincent story (say, 1990 or so) Vincent may already be married and we may have a first communion for his child.

B: Vincent takes control of the old Corleone Family Compound. This brings everything full circle. Terrific opportunities for strong emotional moments (Michael, Connie) perhaps returning to visit Vincent. I can definitely see this.

Let me know if you'd like any help with the Vincent story. I think I may have what you are looking for.