I really like the name Elowen, but [name]Octavia[/name] would be my second choice. I think both work well with [name]Orson[/name].
As for your boys choices, I prefer [name]August[/name].
Good [name]Luck[/name]!
Thanks for so many great replies - I really appreciate all the feedback. (And I am tickled that [name]Pam[/name] herself even responded - thanks for the insights!). Currently a week past my due date and no baby or baby name yet, but we have narrowed it down a bit. I will post an update once the wee one has arrived and has a name.