[name]Hi[/name] there and welcome to Nameberry! First off - Congratulations on your twins! That is like every namers dream!!! 
Now lets take a look at that list of yours:
[name]Madeline[/name] [name]Kaydence[/name] - I like this name but, I would do it a little differently. I would spell it: [name]Madeleine[/name] [name]Cadence[/name]. I have to agree with a previous poster that [name]Kaydence[/name] with a ‘K’ loses some of its meaning for me. Otherwise, I think this one is a lovely choice with some cute nickname options.
[name]Morgan[/name] [name]Marie[/name] - I’m not a lover of alliteration or unisex names (although [name]Sage[/name] I’m sort of in love with). I would switch this one up. Maybe [name]Morgana[/name] [name]June[/name] …
[name]Autumn[/name] [name]Sage[/name] - I like the idea of this name … it might be a little too naturey and in my brain it’s sort of contradictory. When I think of [name]Autumn[/name], I think of reds, oranges, yellows, pumpkins and apples, hay and crisp air. When I think of sage I think of soft [name]Sage[/name] leaves (lightish green), the lovely aroma of sage and of course the meaning of “wise.” To me, these two images mess with me. I’d do one or another and pair each name with a lovely, classic … so something like: [name]Autumn[/name] [name]Elizabeth[/name] or [name]Sage[/name] [name]Caroline[/name].
[name]Emmie[/name] [name]Elizabeth[/name] - [name]Love[/name] this one, even with the alliteration. I would change up the spelling to [name]Emme[/name] [name]Elizabeth[/name].
[name]Phoebe[/name] [name]Noel[/name] - This one is sort of cool - I like the “oe” in [name]Phoebe[/name] that is echoed in the [name]Noel[/name]. I might change it up a little though, just because of the syllable flow (both being 2 syllable names … depending on how many syllables your last name is …).
[name]Willow[/name] [name]Reagan[/name] - The flow again is sort of off for this one. [name]Love[/name] [name]Willow[/name]! What about [name]Willow[/name] [name]June[/name]?
[name]Olivia[/name] [name]Avery[/name] - [name]Love[/name] [name]Olivia[/name] but way way too popular for me. Last year I believe it was the 4th most popular, and I think it is going to be even higher this year (2012 name stats). I know of 4 little Olivias in my immediate friend group who were born in 2012. What about [name]Livia[/name]? It’s an ancient beauty with a similar feel.
[name]Haden[/name] [name]Rebekah[/name] - Not my style at all. I’m sorry. Sticking with the “H” theme … what about [name]Honor[/name] [name]Rebecca[/name]?
[name]Ronan[/name] [name]Nikole[/name] - I’m not a fan of boys names for girls. I would also use the more classic spelling of [name]Nicole[/name] to avoid confusion.
[name]Kyla[/name] [name]Quinn[/name] - I’m not a big fan of [name]Kyla[/name]. [name]Keira[/name] on the other hand … I quite enjoy. Similar feel.
So … my top picks from your list for little ladies are: [name]Madeleine[/name] [name]Cadence[/name], [name]Emme[/name] [name]Elizabeth[/name], [name]Sage[/name] [name]Caroline[/name], [name]Autumn[/name] [name]Elizabeth[/name], [name]Phoebe[/name] [name]Noel[/name], [name]Willow[/name] [name]June[/name], and/or maybe [name]Livia[/name].
Good combo options:
[name]Madeleine[/name]/[name]Madeline[/name] [name]Cadence[/name] and [name]Emme[/name] [name]Elizabeth[/name]
[name]Sage[/name] [name]Caroline[/name] and [name]Willow[/name] [name]June[/name]/[name]Willow[/name] [name]Elizabeth[/name] (Naturey first name with classic middles)
and this one is my own creation: [name]Phoebe[/name] [name]June[/name] and [name]Iris[/name] [name]Caroline[/name] (Greek firsts)
Let us know what you decide!! 