Harry, Thomas, George, James, Joshua, Jack, Oliver, Henry and William.
Ok so you like classic, regal names?
How about Dominic, Patrick, Frederick Benedict, Louis, Gregory, Leo (all the Popes!)
No bible names on your list I notice but if you're not averse to bible names, Saul is also lovely and unusual, but sensible still. Peter would fit into your list above quite seamlessly. So would Richard, maybe with Richie for short. Edward/Teddy is not taken by anybody is it?
Victor springs to mind because of Hugo, but it is a classic quirky name, which I predict will come back within a few years. (on the back of Oscar, Hector and Jaspar). It's cadence is in vogue, if not the actual name, yet.
What about Gus? Classic, simple. Guy?