On your list my favourites are [name_m]Oscar[/name_m], [name_m]Lucas[/name_m], and [name_m]Sebastian[/name_m]. I love the suggestion of [name_u]Jasper[/name_u] for you, and I really like [name_u]Axel[/name_u] but [name_u]Axel[/name_u] and [name_m]Daniel[/name_m] may be a bit close in sound. [name_u]Credence[/name_u] and [name_u]Phoenix[/name_u] feel too far away in style from your other children. I would suggest [name_m]Soren[/name_m] for you.
I like [name_m]Henry[/name_m] and [name_m]Sebastian[/name_m].
With [name_m]Daniel[/name_m] and [name_f]Eleanor[/name_f], I love:
Ezra
[name_m]Josiah[/name_m]
[name_u]Milo[/name_u]
[name_m]Sebastian[/name_m]
Lucas and [name_u]Jordan[/name_u] are super lovely, too; I just don’t like them to quite the degree as the other four. 
What about:
Daniel, [name_f]Eleanor[/name_f], and [name_u]Jude[/name_u]/Judah
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Grant[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Ezekiel[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_u]Holden[/name_u]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Aloysius[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Tor[/name_m]/Torin
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Florin[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Pascal[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Donovan[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Noam[/name_m]
[name_m]Daniel[/name_m], [name_f]Eleanor[/name_f], and [name_m]Felix[/name_m]
Good luck!
I like [name_u]Elliot[/name_u], [name_u]Ezra[/name_u], [name_m]Josiah[/name_m], [name_m]Lucas[/name_m], [name_u]Milo[/name_u], and [name_m]Oscar[/name_m] all work well with the names you already have!