I'm a big fan of Hayden (My DS) and Cooper (his middle name - would have been his first but DH refused flat out to name his son after a car )
My boy's name picks for this one are:
Reuben
Archer
Rowan
Blake
Owen

DH of course doesn't like any of them so we have settled on Evan. Other names we discussed were
Jeremy
Ryan
Robert

I think they all go well with Oliver.

Good luck!