A good friend once said to me that she applied the 'lawyer or rock star' rule when naming her boys - in other words could you imagine the name suiting either. I like that!
My favourites from your boys list are:
Sebastian Jeffrey Fox - sounds very classy, even though I'm not usually a fan of Sebastian
Noah Jeffrey Fox - rock star or lawyer rule applies!
I don't like the others for the following reasons:
Freddie - don't think it's a very serious name 'Freddie Fox', kids book/tv character - I'm also not a fan of alliterative names (is that the right word? Meaning any name beginning with F with a surname of Fox would be a no-no for me)
Oscar - very common here so I would avoid on that basis
Archie - just don't like the name much, no other reason! Strikes up an image of a hapless, eccentric character.
William - again very popular so not keen unless he's going to go thru school career as one of many
Thomas - another very popular one
Stanley - I still think of as rather an old man's name, as well as a bit thuggish maybe?
And fave girls names from your list are:
Absolute fave: Elizabeth Ann Fox - this sounds absolutely lovely, classy and the bonus with Elizabeth is there are so many variations for her to choose from (Beth, Betty, Lizzy, Lizbeth, Liz etc)
Madeleine Ann Fox - I have a Madeleine and I do love the name, it flows well with your middle name and surname too
Eleanor Ann Fox - very soft sounding and flows really nicely
Isobel - as above
Not so keen on the others:
Gracie - very popular at the moment, sounds like a nickname
Phoebe - don't know why but not so keen
Matilda - hard sounding name
Florence - like I said above, I'd avoid 'F' names with an 'F' surname
Evelyn - not bad, more indifferent!
Charlotte - just don't like the name, knew a horrid Charlotte when I was younger...
Poppy - too cute
Rosalie - would almost certainly be shorted to Rosie, which is just too cute in a not so positive way!