Exotic yet familiar and timeless.
I think a name like
William and
Alexander make the name boring.
Although I like the names Whittaker and Ellison I would only use them if they are family names. Otherwise it just looks like another surname.
Gabriel Micah are both Biblical names yet it doesn’t feel religious. Perhaps because I see
Micah more as a modern name rather than Biblical.
I like the one syllable middle names. I suits the longer syllables of
Gabriel.
What about
Gabriel Sebastian?