Okay, first up, I have to say I [name]LOVE[/name] [name]Selene[/name] [name]Liv[/name]!! Or [name]Selene[/name] [name]Olivia[/name], [name]Selene[/name] [name]Livia[/name] or [name]Selene[/name] Lieve ([name]LEE[/name]-vuh) which are other versions that might appeal to you… ^^ [name]Selene[/name] is a fantastic name, with beautiful mythological connections that I wish more people would open their eyes to… She should be more noticed than she is!!
Girls:
[name]Elodie[/name] [name]Rose[/name] - [name]Love[/name] this one, but perhaps use a different mn? [name]Rose[/name] deserves better than to always be the middle… [name]Fern[/name], [name]Lark[/name], [name]Blythe[/name], [name]Plum[/name], [name]Lys[/name], [name]Pearl[/name], [name]Rain[/name], [name]Snow[/name], [name]Wren[/name] and lots of other one syllable names would fit right in, [name]Wren[/name] being a particular favourite ^^
[name]Willa[/name] [name]Clementine[/name] - This one is very spunky, and I like how the long [name]Clementine[/name] balances out the short, nickname-ish [name]Willa[/name]… Very nice!
[name]Selene[/name] [name]Liv[/name] (or [name]Olivia[/name]?) - I think I’ve said enough about this one 
[name]Isabella[/name] [name]Cate[/name] - Although I like [name]Isabella[/name], I don’t like the popularity or the ”ber-girlyness about her. [name]Isobel[/name] is my favourite version of the name… [name]Cate[/name] with a C is refreshing in the middle, and the combo in itself is very melodious! ^^
[name]Georgia[/name] [name]May[/name] - Melts my heart! She’s a sweet one, I’ll tell you that! If it were me choosing from these names, I would have a hard time choosing between her and [name]Selene[/name], but mostly from the family connection… I like [name]Georgia[/name] as a name, but I also find her rather common which irks me a bit…
Boys:
[name]Heath[/name] [name]Brando[/name] - Is intriguing… He takes more getting used to than your other options, but I like him once I get to know him a bit better… I do think [name]Heath[/name] Ledger and [name]Marlon[/name] [name]Brando[/name] however, and I’m not sure that’s a good thing…
[name]James[/name] [name]Jasper[/name] - I can do alliteration, but this sounds like too much, with the ‘Ja’ start to both names, the ‘s’ in both names… [name]Jasper[/name] [name]James[/name] would be better, because [name]Jasper[/name] has more syllables and there’s more air between the two ‘Ja’ parts, and [name]Jasper[/name] is less common…
[name]Noah[/name] [name]Penn[/name] - The sound is good, and I really like it, apart from [name]Noah[/name]'s popularity and tha fact that it somehow seems incomplete? Very abrupt, and perhaps to flowy…
[name]Rufus[/name] [name]Hudson[/name] - This is my favourite of your boys, although I would prefer a less popular middle name with the fantastically unique and spunky [name]Rufus[/name]… ^^
For some other combo suggestions when it comes to your boys:
[name]Rufus[/name] [name]Brando[/name]
[name]Rufus[/name] [name]James[/name]
[name]Rufus[/name] [name]Penn[/name]
[name]Heath[/name] [name]Jasper[/name]
[name]Jasper[/name] [name]Heath[/name]
[name]James[/name] [name]Brando[/name]
[name]Jasper[/name] [name]Penn[/name]
[name]Heath[/name] [name]Noah[/name]
[name]Jasper[/name] [name]Noah[/name] (both names are climbing in popularity, though)
[name]Noah[/name] [name]James[/name]
I don’t really have much more to say about your girls, as I found two perfect combos at least. I’d give you suggestions for other names, but it’s somehow very time consuming for me, and I have a hard time coming up with things myself (I usually resort to nymbler.com, and even then I’m not happy) I think it’s because I know everything about names in keeping with my own style, but have limited knowledge outside of that… I don’t really feel confident making suggestions to people unless they have the same naming style as me, which no one really does as I’m rather eccentric XD
Okay, I have a couple you might like:
[name]Florence[/name]
[name]Flora[/name]
[name]Viola[/name]
[name]Susanna[/name]
[name]June[/name] (perhaps a middle for [name]Elodie[/name]?)
[name]Ida[/name]
[name]Esme[/name]
[name]Edith[/name]
[name]Bryony[/name]
[name]Alva[/name]
[name]Soren[/name]
[name]Rafferty[/name]
[name]Phineas[/name]
[name]Magnus[/name]
Hallam
[name]Ivo[/name]
[name]Lewis[/name]
[name]Samson[/name]
I’m not sure if you’ll like them, but they caught my eye scrolling through my list with your names in my mind… Most of these names are very rare, so no popularity issues ^^
Good luck with deciding, and I hope my insight makes a difference! 
[name]Edit[/name]: Some posting was made while i composed mine, and I just have to say I agree with a lot of [name]Jill[/name]'s suggestions… they’re too popular to be on my list, so I’m not reminded of them often enough to have them pop into mind when trying to suggest something to you… Perhaps I’ll make list of names I love that for some reason or another don’t make it to my list… hmmm…
