Edited for privacy
If you can’t find a middle that you absolutely adore maybe look for what compliments the first name you chose best? One that brings out whatever quality you like about the first name. You have a good while until you really have to decide, I would keep looking on name lists and the family tree until something really pops out. Maybe write down some combos that you like and see how you feel about them in a few months, your views may change on certain names over time 
Any of these options are a good way to handle a mn. For your boy names, you could use [name_m]Henry[/name_m] as a fn or mn for all of them. Similarly, [name_f]Alice[/name_f] works well as a fn for your girl names. I like the idea of honoring family through a mn. If your baby will have your husband’s last name, you could use your maiden/last name as a mn. You don’t necessarily have to use the exact name to honor someone. For instance, you could use [name_f]Moira[/name_f] as a way to honor [name_f]Elenore[/name_f] and [name_f]Mary[/name_f] or [name_f]Marielle[/name_f] to honor [name_f]Mary[/name_f] and [name_u]Lynn[/name_u], etc. For a boy name, [name_m]Jack[/name_m] and [name_m]Ian[/name_m] are both forms of [name_m]John[/name_m] so [name_m]Ian[/name_m] [name_m]David[/name_m] could honor [name_m]Jack[/name_m] and [name_m]David[/name_m]. Or you could use [name_m]Ridge[/name_m] or [name_u]Ellery[/name_u]/[name_u]Eliot[/name_u] to honor [name_m]Eldridge[/name_m].
Some potential combinations:
[name_m]Declan[/name_m] [name_m]Ward[/name_m], [name_m]Declan[/name_m] [name_m]Samuel[/name_m], [name_m]Declan[/name_m] [name_m]Patrick[/name_m]
[name_u]Evan[/name_u] [name_m]Ross[/name_m], [name_u]Evan[/name_u] [name_m]Hamish[/name_m], [name_u]Evan[/name_u] Murdoch
[name_m]Gavin[/name_m] [name_m]Isaac[/name_m], [name_m]Gavin[/name_m] [name_m]Frederick[/name_m], [name_m]Gavin[/name_m] [name_m]Theodore[/name_m]
[name_m]Henry[/name_m] [name_u]Neil[/name_u], [name_m]Henry[/name_m] [name_m]David[/name_m], [name_m]Henry[/name_m] [name_m]Jasper[/name_m]
[name_m]Ian[/name_m] [name_m]Philip[/name_m], [name_m]Ian[/name_m] [name_m]Luke[/name_m], [name_m]Ian[/name_m] [name_m]Gilbert[/name_m]
[name_m]Nathan[/name_m] [name_u]Schuyler[/name_u], [name_m]Nathan[/name_m] [name_m]Ezra[/name_m], [name_m]Nathan[/name_m] [name_u]Lawrence[/name_u]
[name_f]Alice[/name_f] [name_f]Lenore[/name_f], [name_f]Alice[/name_f] [name_f]Miriam[/name_f], [name_f]Alice[/name_f] [name_f]Penelope[/name_f]
[name_f]Bonnie[/name_f] [name_m]Muir[/name_m], [name_f]Bonnie[/name_f] [name_f]Margaret[/name_f], [name_f]Bonnie[/name_f] [name_f]Davina[/name_f]
[name_u]Evelyn[/name_u] [name_f]Frances[/name_f], [name_u]Evelyn[/name_u] [name_f]Mary[/name_f], [name_u]Evelyn[/name_u] [name_f]Sybil[/name_f]
[name_f]Louise[/name_f] [name_f]Margot[/name_f], [name_f]Louise[/name_f] [name_u]Vivian[/name_u], [name_f]Louise[/name_f] [name_f]Tabitha[/name_f]
[name_f]Matilda[/name_f] [name_f]Jane[/name_f], [name_f]Matilda[/name_f] [name_f]Lynette[/name_f], [name_f]Matilda[/name_f] [name_f]Beatrix[/name_f]
[name_u]Ruby[/name_u] [name_f]Nora[/name_f], [name_u]Ruby[/name_u] [name_f]Lenore[/name_f], [name_u]Ruby[/name_u] [name_f]Demetria[/name_f]
As long as you pick a name that you and your SO both like, you can’t really go wrong. I wouldn’t worry too much about whether your family likes the middle name you choose: once they meet the baby they honestly won’t care if the middle name is…say…[name_m]Peregrine[/name_m] ;). They’ll just care about having an adorable baby in the family!
And yes, I agree with what trippindippy said: see what combinations you like, and let that determine your middle name (so it could end up being a family name or a “quirky” name). Two combinations that I really like with the names on your list are [name_f]Alice[/name_f] [name_f]Hermione[/name_f] and [name_m]Nathan[/name_m] [name_m]Ezra[/name_m].
I’ve always been of the opinion that there doesn’t seem to be much point to using a family name unless it means something to you. They are called honor names for a reason, because it’s less about the name than about honoring someone important to you.
It’s pretty common to realize that you are more selective about names when it really hits home that this is the baby and you will be bringing it home to your home now with your life now and your family now not some imagined future when you are younger. I realized as much as I like some names they just didn’t fit us as a family, or even my babies when I did meet them. I think this is definitely a good time to make sib set with full combos to explore how you feel about different middle names. Middles can be a fun place to be more daring or a place to use a name you love but isn’t the right one for a first.
[name_f]Alice[/name_f] Clemetine
[name_m]Declan[/name_m] [name_m]Hamish[/name_m]
[name_u]Ruby[/name_u] Lynore
[name_f]Mary[/name_f] [name_f]Alice[/name_f] Lynore
[name_m]Gavin[/name_m] [name_m]Eldrige[/name_m]
[name_u]Evelyn[/name_u] Mc…