George - A beautiful underused classic. The only caveat is the royal baby.
William - Distinguished, handsome name with lots of nickname options.
Noah - I've just never liked this name.
Aidan - I think this name would probably a favorite of mine if not for the popularity. It's a sweet, upbeat, and fun.
Alexander - Strong name with plenty of nicknames (Lex is my personal fave). Not my favorite, but would go well in the middle.
Nicholas - My favorite of the list. Nicholas is handsome, trustworthy, and an all-around nice guy.
Jack - I don't like this name. I can't explain it, I just don't like it.
Royce - I think it's cool, but doesn't really fit the style and over all tone of the other names.
Tristan - Eh, it's okay. It isn't bad, but it isn't one of my favorites.
Sebastian - Fun, interesting name on it's own, but I don't like any of the nicknames.
With George just being used by the royal family I would not use that as a first name.
I'm not sure where you're from but here these names are over used, Noah coming in second in the top 100 list. If that doesn't bother you then I put my vote on these combinations!
Sawyer came to mind when I read your list of names. Maybe you like it...