I'm exactly the same as you OP, in that I'd mostly settled on a (less common/popular) girls name I loved quite easily, so expected to feel the same about a boys name when I found out I was having a DS instead.
As a name lover I thought I'd go for something more unusual too (I liked names like Orlando, Zev, Bram, Ivo, Heath etc), but now that he's getting closer to arriving I've turned to more traditional names instead - William, Alexander, Hugh, Edward, Samuel and James are some of the names on my list now! (John, Thomas etc would be there too but they are already used by close family members)
For me of your choices, I'm probably drawn towards John the most - it used to be so popular that there are some amazing historical namesakes but it's much less common now, so he'll probably be the only one in his class/groups. Plus I like both it's nn's Johnny and Jack so that's a bonus, as you can never tell if he'll get a nickname.
Edward is my second choice and may be the "safer" timeless option since it's never left the top 100 in popularity. But I'm less keen on Ed/Eddie (of the many Edward nn options) which personally puts me off a bit.