From your list, I like [name_m]Landon[/name_m] and [name_m]Jude[/name_m] for a boy and [name_f]Luna[/name_f] and [name_f]Zoe[/name_f] for a girl.
[name_f][/name_f]More suggestions:
[name_f][/name_f][name_f]Aria[/name_f]
[name_f][/name_f][name_f]Bria[/name_f] (similar to [name_f]Bea[/name_f] but more modern)
[name_f][/name_f][name_f]Eden[/name_f]
[name_f][/name_f][name_f]Elle[/name_f] (more modern than Nellie)
[name_f][/name_f][name_f]Freya[/name_f] (similar in sound to Leyla)
[name_f][/name_f][name_f]Gemma[/name_f]
[name_f][/name_f][name_f]Lucia[/name_f] (fits [name_f]Mila[/name_f] and [name_f]Sienna[/name_f] more than Lucy)
[name_f][/name_f][name_f]Lyra[/name_f]
[name_f][/name_f][name_f]Poppy[/name_f]
[name_f][/name_f][name_f]Willow[/name_f]
[name_m]Boston[/name_m] (similar to Brooklyn)
[name_f][/name_f][name_m]Cash[/name_m]
[name_f][/name_f][name_m]Elio[/name_m] (has Leo’s sound in it)
[name_f][/name_f][name_m]Jem[/name_m]
[name_f][/name_f][name_m]Linus[/name_m]
[name_f][/name_f][name_m]Luca[/name_m]
[name_f][/name_f][name_m]Nico[/name_m]
[name_f][/name_f][name_m]Rex[/name_m] (rhymes with Lex)
[name_f][/name_f][name_m]Theron[/name_m]
[name_f][/name_f][name_m]Waylon[/name_m]
[name_f]Hope[/name_f] this helps!