Smamfa - I love love love ALL of your names! I would personally not use Zachary, I know if you love it you should use it but I think I would want my child to have its own identity and not have people possibly confused when talking about the cousins. Sorry, I know I am going against what most people have said - please take my thoughts and opinions with a pinch of salt!

Out of the other 3, my faves are in this order: Ollie, Wil, Gabe.

But seriously - all awesome names, your little boy is going to be soooo lucky whatever you decide on