Congrats!
I like [name_f]Vista[/name_f], not so keen on [name_m]Knox[/name_m] - not only bc masculine when your other names more neutral to the gender they’re being used for, but I just don’t think it’s as spunky or ethereal as your others! I also think it could be a tad annoying to have people assume [name_m]Knox[/name_m] is the lone boy.
My only teeny reservation with [name_f]Vista[/name_f] though, is that it is a brand and also my brain then makes Sunsen, sunset (ie a lovely vista).
How about:
[name_m]Jem[/name_m]
[name_f]Naia[/name_f]
[name_f]Lumi[/name_f]
[name_f]Vega[/name_f]
[name_f]Veda[/name_f]
[name_f]Indy[/name_f]
[name_f]Fleur[/name_f]
[name_f]Kirra[/name_f]
[name_f]Tova[/name_f]
[name_f]Delta[/name_f]
[name_f]Leda[/name_f]
[name_f]Fifer[/name_f]
Zoan (Zo’un)
[name_f]Paloma[/name_f]
[name_f]Roisin[/name_f] (Ro-sheen)
And I also really like [name_f]Mara[/name_f], [name_f]Xanthe[/name_f] and [name_f]Lurleen[/name_f]!