[name]Thea[/name] [name]Juliette[/name]: I think this is absolutely stunning! [name]How[/name] are you pronouncing [name]Thea[/name]? Thee-uh, [name]Thay[/name]-uh, or [name]Tay[/name]-uh?
[name]Jonas[/name] [name]Daniel[/name]: I do think of the [name]Jonas[/name] brothers, and I wonder if he’ll constantly have to deal with people asking him if he was named after the [name]Jonas[/name] Brothers. I do think it’s a handsome name, though.
[name]Norah[/name] [name]Desiree[/name]: I love [name]Nora[/name] ([name]Eleanora[/name] and [name]Eleanor[/name], too), and personally prefer it without the h. I’m personally not a fan of [name]Desiree[/name], and to me, it sticks out from the other lovely names you’ve listed.
I love how [name]Thea[/name], [name]Jonas[/name], and [name]Nora[/name] all have the same two syllable format ending with an a sound, without feeling too matchy.
I’m really sorry about your dad having passed away, and think it’s wonderful that you’ll be naming a baby after him.
Some other options for honoring [name]Denis[/name], not all of which will work with [name]Nora[/name]:
A middle name ending in [name]DEN[/name]:
[name]Arden[/name] (different from the other names on your list, though)
[name]Auden[/name] (ditto)
[name]Eden[/name] (Different in style from the others, but yet exotic like [name]Thea[/name] and [name]Juliette[/name])
Names that contain the letters in [name]Denis[/name]:
[name]Sandrine[/name] (French for [name]Alexandra[/name], but as [name]Pam[/name] and [name]Linda[/name] pointed out, also the name of a chemical.)
[name]Roselind[/name] (normally spelled with an A, but I know that [name]Roselind[/name] is a legitimate variation)
D names to honor [name]Denis[/name]’ initial:
[name]Diana[/name]
[name]Dinah[/name] (could work in place of [name]Norah[/name] up front)
[name]Daisy[/name]
[name]Delilah[/name]
[name]Dorothea[/name] (nn [name]Thea[/name], instead of just [name]Thea[/name], but wouldn’t flow with [name]Juliette[/name])
[name]Dahlia[/name]
[name]Dilys[/name] (sounds a lot like [name]Denis[/name])
For a boy, D for [name]Daniel[/name] could honor [name]Denis[/name], as well as:
[name]Dennison[/name] (works with [name]Jonah[/name] as a first name)
[name]Dennet[/name]
[name]Dashiell[/name]
[name]Davis[/name]
[name]Dexter[/name]
(Not all work with [name]Jonas[/name], though…)
Good luck!